Language：Japanese   Publisher：JAMA Network Open  

DOI： 10.1001/jamanetworkopen.2021.41768

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Language：Japanese   Publisher：Psychiatry and Clinical Neurosciences  

DOI： 10.1111/pcn.13309

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PubMed

Language：Japanese   Publisher：BMC Psychiatry  

Background: Esketamine nasal spray (Spravato) in conjunction with oral antidepressants (ADs) is approved in the European Union, United States, and other markets for treatment-resistant depression (TRD). Efficacy, safety, and tolerability of esketamine nasal spray in Japanese patients with TRD needs to be assessed. Methods: This Phase 2b, randomized, double-blind (DB), placebo-controlled study was conducted in adult Japanese patients with TRD meeting the Diagnostic and Statistical Manual of Mental Disorders (fifth edition) criteria of major depressive disorder with nonresponse to ≥ 1 but < 5 different ADs in the current episode at screening. Patients were treated with a new oral AD for 6 weeks (prospective lead-in phase); nonresponders were randomized (2:1:1:1) to placebo or esketamine (28-, 56-, or 84-mg) nasal spray along with the continued use of AD for 4 weeks (DB induction phase). Responders (≥50% reduction from baseline in the Montgomery-Asberg Depression Rating Scale [MADRS] total score) from the DB induction phase continued into the 24-week posttreatment phase and patients who relapsed could participate in a 4-week open-label (OL) second induction (flexibly-dosed esketamine). The primary efficacy endpoint, change from baseline in the MADRS total score at Day 28 in the DB induction phase, was based on mixed-effects model using repeated measures pairwise comparisons using a Dunnett adjustment. Results: Of the 202 patients randomized in the DB induction phase (esketamine [n = 122] or placebo [n = 80]), the MADRS total scores decreased from baseline to Day 28 of the DB induction phase (− 15.2, − 14.5, − 15.1, and − 15.3 for esketamine 28 mg, 56 mg, 84 mg, and placebo groups, respectively), indicating an improvement in depressive symptoms; however, the difference between the esketamine and placebo groups was not statistically significant. The most common treatment-emergent adverse events during the DB induction phase in the combined esketamine group (incidences ranging from 12.3 to 41.0%) were blood pressure increased, dissociation, dizziness, somnolence, nausea, hypoaesthesia, vertigo, and headache; the incidence of each of these events was > 2-fold higher than the corresponding incidence in the placebo group. Conclusions: Efficacy of esketamine plus oral AD in Japanese TRD patients was not established; further investigation is warranted. All esketamine doses were safe and tolerated. Trial registration: ClinicalTrials.gov Identifier: NCT02918318. Registered: 28 September 2016.

DOI： 10.1186/s12888-021-03538-y

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Publisher：株式会社医学書院  

DOI： 10.11477/mf.1405206315

CiNii Research

Language：English   Publisher：Frontiers in Psychiatry  

Introduction: Accumulating evidence has shown that maternal metabolic conditions, such as pre-pregnancy overweight, diabetes mellitus, and hypertensive disorders of pregnancy (HDP) are potential risk factors of autism spectrum disorder (ASD). However, it remains unclear how these maternal conditions lead to neurodevelopmental outcomes in the offspring, including autistic symptoms. Leptin, an adipokine that has pro-inflammatory effects and affects fetal neurodevelopment, is a candidate mediator of the association between maternal metabolic factors and an increased risk of ASD. However, whether prenatal exposure to leptin mediates the association between maternal metabolic conditions and autistic symptoms in children has not been investigated yet. Methods: This study investigated the associations between mothers' metabolic conditions (pre-pregnancy overweight, diabetes mellitus during or before pregnancy, and HDP), leptin concentrations in umbilical cord serum, and autistic symptoms among 762 children from an ongoing cohort study, using generalized structural equation modeling. We used the Social Responsive Scale, Second Edition (SRS-2) at 8–9 years old to calculate total T-scores. Additionally, we used the T-scores for two subdomains: Social Communication and Interaction (SCI) and Restricted Interests and Repetitive Behavior (RRB). Results: Umbilical cord leptin levels were associated with pre-pregnancy overweight [coefficient = 1.297, 95% confidence interval (CI) 1.081–1.556, p = 0.005] and diabetes mellitus (coefficient = 1.574, 95% CI 1.206–2.055, p = 0.001). Furthermore, leptin levels were significantly associated with SRS-2 total T-scores (coefficient = 1.002, 95% CI 1.000–1.004, p = 0.023), SCI scores (coefficient = 1.002, 95% CI 1.000–1.004, p = 0.020), and RRB scores (coefficient = 1.001, 95% CI 1.000–1.003, p = 0.044) in children. Associations between maternal metabolic factors and autistic symptoms were not significant. Discussion: The present study uncovered an association between cord leptin levels and autistic symptoms in children, while maternal metabolic conditions did not have an evident direct influence on the outcome. These results imply that prenatal pro-inflammatory environments affected by maternal metabolic conditions may contribute to the development of autistic symptoms in children. The findings warrant further investigation into the role of leptin in the development of autistic symptoms.

DOI： 10.3389/fpsyt.2021.816196

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Language：Japanese   Publisher：The Japanese Society of Toxicology  

<p>Two neurodevelopmental disorders, autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD), become apparent in infancy and have diverse prognoses. </p><p>Both genetic and environmental risk factors contribute to the emergence of ASD and ADHD. Such environmental risk factors include nutrient deficiencies, heavy metals, alcohol, diesel exhaust particles, residual organic pollutants, pesticides and agricultural chemicals in the womb and during neonatal period as well as exposure to digital devices during early infancy.</p><p>The author will discuss how these findings should be interpreted from the perspective of child psychiatry and epidemiology.</p>

DOI： 10.14869/toxpt.48.1.0_s16-4

CiNii Research

Publisher：金原出版  

DOI： 10.18888/sp.0000001176

CiNii Research

Language：Japanese  

PubMed

Language：English  

DOI： 10.1097/WNR.0b013e3282f600b4

PubMed

Language：English  

PubMed

Language：Japanese  

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Language：English  

DOI： 10.1159/000100777

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

<title>Abstract</title><sec>
<title>Background</title>
Both genetic and pre- and perinatal factors, including birth weight, have been implicated in the onset of attention deficit hyperactivity disorder (ADHD) traits among children. This study aimed to elucidate to what extent the genetic risk of ADHD moderates the association between birth weight and ADHD traits among Japanese children.


</sec><sec>
<title>Methods</title>
We conducted a longitudinal birth cohort study (Hamamatsu Birth Cohort for Mother and Children Study) to investigate the association of genetic risk for ADHD and low birth weight with ADHD traits among Japanese children. Out of 1258 children<bold>,</bold> we included 796 who completed follow-ups at 8 to 9 years of age. Birth weight was categorized as &lt;2000 g, 2000–2499 g, and ≥2500 g. Polygenic risk score for ADHD was generated using the summary data of a large-scale genome-wide association study. The Rating Scale IV (ADHD-RS) assessed ADHD traits (inattention and hyperactivity/impulsivity) based on parental reports. Following previous studies, sex, birth order of the child, gestational age at birth, mother’s age at delivery, educational attainment, pre-pregnancy body mass index, pre-pregnancy or during pregnancy smoking status, alcohol consumption during pregnancy, father’s age, education, and annual family income were considered as covariates. Multivariable negative binomial regression was applied to evaluate the association between birth weight and ADHD traits, while adjusting for potential covariates. The interaction term between birth weight categories and binary polygenic risk was added to the model.


</sec><sec>
<title>Results</title>
Birth weight of 2000–2499 g was not associated with ADHD traits. Birth weight under 2000 g was significantly associated with both inattention and hyperactivity. When accounting for higher and lower genetic risk for ADHD, only those with higher genetic risk and birth weight &lt; 2000 g were associated with inattention (rate ratio [RR] 1.56, 95% CI 1.07–2.27) and hyperactivity (RR 1.87, 95% CI 1.14–3.06)<bold>.</bold>


</sec><sec>
<title>Conclusions</title>
Birth weight under 2000 g, together with the genetic risk of ADHD, contributes to higher levels of ADHD traits among Japanese children aged 8 to 9 years. The suggested association between low birth weight and ADHD is confined to children with a genetic susceptibility to ADHD, indicating the relevance of genetic-environmental interactions in the etiology.


</sec>

DOI： 10.1186/s12916-021-02093-3

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PubMed

Other Link： https://link.springer.com/article/10.1186/s12916-021-02093-3/fulltext.html

Language：Japanese   Publishing type：Research paper (scientific journal)  

Attention-deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders, characterized by a persistent pattern of inattention, hyperactivity, and impulsivity. Since the diagnosis of ADHD is defined by operational diagnostic criteria consisting of several clinical symptoms, a number of heterogeneous mechanisms have been considered to be implicated in its pathophysiology. Although no clinically reliable biomarkers are available for the diagnosis of ADHD, several plausible candidate biomarkers have been proposed based on recent advances in biochemistry and molecular biology. This review article summarizes potential peripheral biomarkers associated with ADHD, mainly from recently published case-control studies. These include 1) biochemical markers: neurotransmitters and their receptors, neurotrophic factors, serum electrolytes, and inflammation markers; 2) genetic and epigenetic markers: microRNA, mRNA expression, and peripheral DNA methylation; 3) physiological markers: eye movement and electroencephalography. It also discusses the limitations and future directions of these potential biomarkers for application in clinical practice.

DOI： 10.1016/j.jpsychires.2021.03.012

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Frontiers Media SA  

<bold>Introduction:</bold> Obesity is highly heritable, and recent evidence demonstrates that obesity is associated with cognitive deficits, specifically working memory. However, the relationship between genetic risks for obesity and working memory is not clear. In addition, whether the effect of these genetic risks on working memory in children is mediated by increased body mass index (BMI) has not been elucidated.

<bold>Methods:</bold> In order to test whether the polygenic risk score (PRS) for obesity in adulthood (adulthood-BMI-PRS) is associated with working memory at 8 years of age, and whether the effect is mediated by childhood BMI, in children from the general population, participants in the Hamamatsu Birth Cohort for Mothers and Children (HBC) study in Hamamatsu, Japan, underwent testing for association of adulthood-BMI-PRS with working memory. HBC data collection began in December 2007 and is ongoing. Adulthood-BMI-PRS values were generated using summary data from the recent genome-wide association study (GWAS) undertaken in Japan, and the significance of thresholds was calculated for each outcome. Outcomes measured included the working memory index (WMI) of Weschler Intelligence Scale-4 (WISC-IV) scores and the BMI at 8 years of age. Gene-set enrichment analysis was conducted to clarify the molecular basis common to adulthood-BMI and childhood-WMI. Mediation analysis was performed to assess whether childhood-BMI of children mediated the association between adulthood-BMI-PRS and working memory.

<bold>Results:</bold> A total of 734 participants (377 males, 357 females) were analyzed. Adulthood-BMI-PRS was associated with lower childhood-WMI (β[SE], −1.807 [0.668]; <italic>p</italic> = 0.010, corrected) of WISC-IV. Gene-set enrichment analyses found that regulation of neurotrophin Trk receptor signaling (β[SE], −2.020 [6.39]; <italic>p</italic> = 0.002, corrected), negative regulation of GTPase activity (β[SE], 2.001 [0.630]; <italic>p</italic> = 0.002, corrected), and regulation of gene expression epigenetic (β[SE], −2.119 [0.664]; <italic>p</italic> = 0.002, corrected) were enriched in BMI in adulthood and WMI in childhood. Mediation analysis showed that there is no mediation effect of childhood-BMI between the adulthood-BMI-PRS and working memory deficits in children.

<bold>Conclusion:</bold> Adulthood-BMI-PRS was associated with working memory among children in the general population. These genetic risks were not mediated by the childhood-BMI itself and were directly associated with working memory deficits.

DOI： 10.3389/fnins.2021.749230

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Language：English   Publishing type：Research paper (scientific journal)  

Attention deficit hyperactive disorder (ADHD) is a highly heritable neurodevelopmental disorder, and excessive daytime sleepiness is frequently observed in ADHD patients. Excessive daytime sleepiness is also a core symptom of narcolepsy and essential hypersomnia (EHS), which are also heritable conditions. Psychostimulants are effective for the symptomatic control of ADHD (primary recommended intervention) and the two sleep disorders (frequent off-label use). However, the common biological mechanism for these disorders has not been well understood. Using a previously collected genome-wide association study of narcolepsy and EHS, we calculated polygenic risk scores (PRS) for each individual. We investigated a possible genetic association between ADHD and narcolepsy traits in the Hamamatsu Birth Cohort for mothers and children (HBC study) (n = 876). Gene-set enrichment analyses were used to identify common pathways underlying these disorders. Narcolepsy PRS were significantly associated with ADHD traits both in the hyperactivity domain (e.g., P-value threshold < 0.05, β [SE], 5.815 [1.774]; P = 0.002) and inattention domain (e.g., P-value threshold < 0.05, β [SE], 5.734 [1.761]; P = 0.004). However, EHS PRS was not significantly associated with either domain of ADHD traits. Gene-set enrichment analyses revealed that pathways related to dopaminergic signaling, immune systems, iron metabolism, and glial cell function involved in both ADHD and narcolepsy. Findings indicate that ADHD and narcolepsy are genetically related, and there are possible common underlying biological mechanisms for this relationship. Future studies replicating these findings would be warranted to elucidate the genetic vulnerability for daytime sleepiness in individuals with ADHD.

DOI： 10.1038/s41398-020-00971-7

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Language：English   Publishing type：Research paper (scientific journal)  

Importance: Autism spectrum disorder (ASD) is highly heritable, and modest contributions of common genetic variants to ASD have been reported. However, the association of genetic risks derived from common risk variants with ASD traits in children from the general population is not clear, and the association of these genetic risks with neurodevelopment in infants has not been well understood. Objective: To test whether a polygenic risk score (PRS) for ASD is associated with neurodevelopmental progress at age 18 months and ASD traits at age 6 years among children from the general population. Design, Setting, and Participants: In this cohort study, 876 children in the Hamamatsu Birth Cohort for Mothers and Children in Hamamatsu, Japan, underwent testing for the association of an ASD PRS with neurodevelopmental progress and ASD traits. Data collection began in December 2007 and is ongoing. Data analysis was conducted from April to December 2019. Main Outcomes and Measures: Summary data from the largest genome-wide association study were used to generate ASD PRSs, and significance of thresholds was calculated for each outcome. The Autism Diagnostic Observation Schedule 2 was used to measure ASD traits at age 6 years, and the Mullen Scales of Early Learning was used to measure neurodevelopmental progress at age 18 months. Results: Of 876 participants (mean [SD] gestational age at birth, 38.9 [1.6] weeks; 438 [50.0%] boys; 868 [99.1%] Japanese), 734 were analyzed. The ASD PRS was associated with ASD traits (R2 = 0.024; β, 0.71; SE, 0.24; P = .03). The association of ASD PRS with infant neurodevelopment was most pronounced in gross motor (R2 = 0.015; β, -1.25; SE, 0.39; P = .01) and receptive language (R2 = 0.014; β, -1.19; SE, 0.39; P = .02) scores on the Mullen Scales of Early Learning. Gene set enrichment analyses found that several pathways, such as cell maturation (R2 = 0.057; β, -5.28; SE, 1.40; P < .001) and adenylyl cyclase activity and cyclic adenosine monophosphate concentration (R2 = 0.064; β, -5.30; SE 1.30; P < .001), were associated with ASD traits. Gene sets associated with inflammation were commonly enriched with ASD traits and gross motor skills (eg, chemokine motif ligand 2 production: R2 = 0.051; β, -6.04; SE, 1.75; P = .001; regulation of monocyte differentiation: R2 = 0.052; β, -6.63; SE, 1.90; P = .001; and B-cell differentiation: R2 = 0.051; β, 7.37; SE, 2.15; P = .001); glutamatergic signaling-associated gene sets were commonly enriched with ASD traits and receptive language skills (eg, regulation of glutamate secretion: R2 = 0.052; β, -5.82; SE, 1.68; P = .001; ionotropic glutamate receptor signaling pathway: R2 = 0.047; β, 3.54; SE, 1.09; P = .001; and negative regulation of glutamate secretion: R2 = 0.045; β, -5.38; SE, 1.74; P = .002). Conclusions and Relevance: In this study, the ASD PRS was associated with ASD traits among children from the general population. Genetic risks for ASD might be associated with delays in some neurodevelopmental domains, such as gross motor and receptive language skills.

DOI： 10.1001/jamanetworkopen.2019.21644

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PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：COMPANY OF BIOLOGISTS LTD  

Central arginine vasopressin receptor 1A(AVPR1A) modulates a wide range of behaviors, including stress management and territorial aggression, as well as social bonding and recognition. Inter- and intra-species variations in the expression pattern of AVPR1A in the brain and downstream differential behavioral phenotypes have been attributed to differences in the non-coding regions of the AVPR1A gene, including polymorphic elements within upstream regulatory areas. Gene association studies have suggested a link between AVPR1A polymorphisms and autism, and AVPR1A has emerged as a potential pharmacological target for treatment of social cognitive impairments and mood and anxiety disorders. To further investigate the genetic mechanism giving rise to species differences in AVPR1A expression patterns and associated social behaviors, and to create a preclinical mouse model useful for screening drugs targeting AVPR1A, we engineered and extensively characterized bacterial artificial chromosome(BAC) transgenic mice harboring the entire human AVPR1A locus with the surrounding regulatory elements. Compared with wild-type animals, the humanized mice displayed a more widely distributed ligand-AVPR1A binding pattern, which overlapped with that of primates. Furthermore, humanized AVPR1A mice displayed increased reciprocal social interactions compared with wild-type animals, but no differences in social approach and preference for social novelty were observed. Aspects of learning and memory, specifically novel object recognition and spatial relocation recognition, were unaffected. The biological alterations in humanized AVPR1A mice resulted in the rescue of the prepulse inhibition impairments that were observed in knockout mice, indicating conserved functionality. Although further behavioral paradigms and additional cohorts need to be examined in humanized AVPR1A mice, the results demonstrate that species-specific variations in the genomic content of regulatory regions surrounding the AVPR1A locus are responsible for differential receptor protein expression patterns across species and that they are likely to contribute to species-specific behavioral variation. The humanized AVPR1A mouse is a potential preclinical model for further understanding the regulation of receptor gene expression and the impact of variation in receptor expression on behaviors, and should be useful for screening drugs targeting human AVPR1A, taking advantage of the expression of human AVPR1A in human-relevant brain regions.

DOI： 10.1242/dmm.017053

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Language：English   Publishing type：Research paper (scientific journal)  

OBJECTIVES: To evaluate the safety and efficacy of osmotic-controlled release oral delivery system (OROS) methylphenidate (MPH) HCl in adults with attention-deficit/hyperactivity disorder (ADHD). METHODS: In this study, 284 adults with ADHD were randomized to OROS MPH or placebo. During the 4-week titration period, patients were titrated from a starting dose of 18 mg once daily to an individually-optimized dose of up to 72 mg once daily in weekly 18-mg increments. Patients continued on their individualized dose during the 4-week efficacy assessment period. The primary efficacy endpoint was change in DSM-IV Total ADHD Symptoms subscale score of Conners' Adult ADHD Rating Scale-Observer: Screening Version (CAARS-O:SV) from baseline to endpoint. RESULTS: The mean change in DSM-IV Total ADHD Symptoms subscale score of CAARS-O:SV was significantly larger with OROS MPH compared with placebo (P < 0.0001, ANCOVA). Similar results were observed for the majority of secondary endpoints, including CAARS-O:SV total score and other subscale scores. Although treatment-emergent adverse events were reported more frequently in the OROS MPH group (81.8%) versus the placebo group (53.9%), OROS-MPH showed a well-tolerated safety profile overall. CONCLUSIONS: OROS MPH in a dose range of 18-72 mg once daily was effective and well-tolerated in adult patients with ADHD.

DOI： 10.3109/15622975.2013.868925

PubMed

Language：Japanese  

Glial cells consisting of oligodendrocytes, astrocytes, microglia, and NG2 positive cells are major cell populations in the central nervous system, number-wise. They function as effectors and modulators of neurodevelopment through a wide variety of neuron-glial cell interactions in brain development and functions. Glial cells can be affected by both genetic and environmental factors, leading to their dysfunctions in supporting neuronal development and functions. These in turn can affect neuronal cells, causing alterations at the circuitry level that manifest as behavioral characteristics associated with schizophrenia in late teens-early twenties. Glial cells are also involved in neuroinflammatory processes, which sometimes have deleterious effects on the normal brain development. If the glial involvement plays significant roles in schizophrenia, the processes involving glial cells can become possible therapeutic targets for schizophrenia. A number of known antipsychotics are shown to have beneficial effects on glial cells, but other drugs targeting glial cell functions may also have therapeutic effects on schizophrenia. The latter can be taken into consideration for future drug development for schizophrenia.

DOI： 10.1016/j.nbd.2012.11.001

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Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: This 13-week, double-blind study was conducted to confirm the efficacy and safety of paliperidone palmitate (PP), at dosing regimens approved in other countries, in Asian patients with schizophrenia. METHODS: Asian patients (aged ≥20 years) diagnosed with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-Text Revision criteria), and having a Positive and Negative Syndrome Scale (PANSS) total score of 60 to 120 were enrolled and randomized (1:1) to a PP or placebo group. Patients received PP intramuscularly at recommended doses: initiation dose 150 mg equivalent (eq) PP on day 1 and 100 mg eq PP on day 8 (deltoid); and a monthly maintenance dose of 75 mg eq PP on days 36 and 64 (deltoid or gluteal). The change from baseline to week 13 in PANSS total scores (primary endpoint), Clinical Global Impression-Severity (CGI-S) scores, and PANSS Marder factor scores and subscales, and responder rate at week 13 were evaluated. Safety was also assessed. RESULTS: The PANSS total score (P<0.0001, least-squares mean change from baseline to week 13: PP, -3.5; placebo, +6.2), CGI-S score (P<0.0001), and PANSS Marder factor scores (P≤0.0025) were significantly improved at week 13 in the PP group versus placebo. More treatment responders (≥30% decrease in PANSS total score) were in the PP group (22.8%) versus placebo (8.5%). Insomnia (PP 17.0% versus placebo 15.2%), injection site pain (13.2% versus 6.7%), nasopharyngitis (12.6% versus 6.1%), psychiatric symptoms (11.3% versus 26.2%), and extrapyramidal symptoms (10.1% versus 4.9%) were the most frequently occurring treatment-emergent adverse events. CONCLUSION: PP is efficacious for Asian patients with schizophrenia at the dosing regimen approved in other countries, with a similar safety and tolerability profile.

DOI： 10.2147/NDT.S54051

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Longevity has a strong genetic component evidenced by family-based studies. Lipoprotein metabolism, FOXO proteins, and insulin/IGF-1 signaling pathways in model systems have shown polygenic variations predisposing to shorter lifespan. To test the hypothesis that rare variants could influence lifespan, we compared the rates of CNVs in healthy children (0-18 years of age) with individuals 67 years or older. CNVs at a significantly higher frequency in the pediatric cohort were considered risk variants impacting lifespan, while those enriched in the geriatric cohort were considered longevity protective variants. We performed a whole-genome CNV analysis on 7,313 children and 2,701 adults of European ancestry genotyped with 302,108 SNP probes. Positive findings were evaluated in an independent cohort of 2,079 pediatric and 4,692 geriatric subjects. We detected 8 deletions and 10 duplications that were enriched in the pediatric group (P=3.33×10(-8)-1.6×10(-2) unadjusted), while only one duplication was enriched in the geriatric cohort (P=6.3×10(-4)). Population stratification correction resulted in 5 deletions and 3 duplications remaining significant (P=5.16×10(-5)-4.26×10(-2)) in the replication cohort. Three deletions and four duplications were significant combined (combined P=3.7×10(-4)-3.9×10(-2)). All associated loci were experimentally validated using qPCR. Evaluation of these genes for pathway enrichment demonstrated ~50% are involved in alternative splicing (P=0.0077 Benjamini and Hochberg corrected). We conclude that genetic variations disrupting RNA splicing could have long-term biological effects impacting lifespan.

DOI： 10.1371/journal.pone.0053846

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Language：English   Publishing type：Research paper (scientific journal)  

Histone deacetylases (HDACs) compact chromatin structure and repress gene transcription. In schizophrenia, clinical studies demonstrate that HDAC inhibitors are efficacious when given in combination with atypical antipsychotics. However, the molecular mechanism that integrates a better response to antipsychotics with changes in chromatin structure remains unknown. Here we found that chronic atypical antipsychotics downregulated the transcription of metabotropic glutamate 2 receptor (mGlu2, also known as Grm2), an effect that was associated with decreased histone acetylation at its promoter in mouse and human frontal cortex. This epigenetic change occurred in concert with a serotonin 5-HT(2A) receptor-dependent upregulation and increased binding of HDAC2 to the mGlu2 promoter. Virally mediated overexpression of HDAC2 in frontal cortex decreased mGlu2 transcription and its electrophysiological properties, thereby increasing psychosis-like behavior. Conversely, HDAC inhibitors prevented the repressive histone modifications induced at the mGlu2 promoter by atypical antipsychotics, and augmented their therapeutic-like effects. These observations support the view of HDAC2 as a promising new target for schizophrenia treatment.

DOI： 10.1038/nn.3181

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PUBLIC LIBRARY SCIENCE  

BACKGROUND: Copy number variation (CNV) at the 15q11.2 region, which includes a gene that codes for CYFIP1 (cytoplasmic FMR1 interacting protein 1), has been implicated in autism, intellectual disability and additional neuropsychiatric phenotypes. In the current study we studied the function of Cyfip1 in synaptic physiology and behavior, using mice with a disruption of the Cyfip1 gene. METHODOLOGY/PRINCIPAL FINDINGS: We observed that in Cyfip1 heterozygous mice metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD) induced by paired-pulse low frequency stimulation (PP-LFS) was significantly increased in comparison to wildtype mice. In addition, mGluR-LTD was not affected in the presence of protein synthesis inhibitor in the Cyfip1 heterozygous mice, while the same treatment inhibited LTD in wildtype littermate controls. mGluR-agonist (RS)-3,5-dihydroxyphenylglycine (DHPG)-induced LTD was also significantly increased in hippocampal slices from Cyfip1 heterozygous mice and again showed independence from protein synthesis only in the heterozygous animals. Furthermore, we observed that the mammalian Target of Rapamycin (mTOR) inhibitor rapamycin was only effective at reducing mGluR-LTD in wildtype animals. Behaviorally, Cyfip1 heterozygous mice showed enhanced extinction of inhibitory avoidance. Application of both mGluR5 and mGluR1 antagonist to slices from Cyfip1 heterozygous mice reversed the increase in DHPG-induced LTD in these mice. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that haploinsufficiency of Cyfip1 mimics key aspects of the phenotype of Fmr1 knockout mice and are consistent with the hypothesis that these effects are mediated by interaction of Cyfip1 and Fmrp in regulating activity-dependent translation. The data provide support for a model where CYFIP1 haploinsufficiency in patients results in intermediate phenotypes increasing risk for neuropsychiatric disorders.

DOI： 10.1371/journal.pone.0042422

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NATURE PUBLISHING GROUP  

Attention deficit hyperactivity disorder (ADHD) is a common, heritable neuropsychiatric disorder of unknown etiology. We performed a whole-genome copy number variation (CNV) study on 1,013 cases with ADHD and 4,105 healthy children of European ancestry using 550,000 SNPs. We evaluated statistically significant findings in multiple independent cohorts, with a total of 2,493 cases with ADHD and 9,222 controls of European ancestry, using matched platforms. CNVs affecting metabotropic glutamate receptor genes were enriched across all cohorts (P = 2.1 x 10(-9)). We saw GRM5 (encoding glutamate receptor, metabotropic 5) deletions in ten cases and one control (P = 1.36 x 10(-6)). We saw GRM7 deletions in six cases, and we saw GRM8 deletions in eight cases and no controls. GRM1 was duplicated in eight cases. We experimentally validated the observed variants using quantitative RT-PCR. A gene network analysis showed that genes interacting with the genes in the GRM family are enriched for CNVs in similar to 10% of the cases (P = 4.38 x 10(-10)) after correction for occurrence in the controls. We identified rare recurrent CNVs affecting glutamatergic neurotransmission genes that were overrepresented in multiple ADHD cohorts.

DOI： 10.1038/ng.1013

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Language：English   Publishing type：Research paper (scientific journal)  

Background: Solid evidence links schizophrenia (SZ) susceptibility to neurodevelopmental processes involving tyrosine phosphorylation-mediated signaling. Mouse studies implicate the Ptpra gene, encoding protein tyrosine phosphatase RPTPα, in the control of radial neuronal migration, cortical cytoarchitecture, and oligodendrocyte differentiation. The human gene encoding RPTPα, PTPRA, maps to a chromosomal region (20p13) associated with susceptibility to psychotic illness. Methods: We characterized neurobehavioral parameters, as well as gene expression in the central nervous system, of mice with a null mutation in the Ptpra gene. We searched for genetic association between polymorphisms in PTPRA and schizophrenia risk (two independent cohorts, 1420 cases and 1377 controls), and we monitored PTPRA expression in prefrontal dorsolateral cortex of SZ patients (35 cases, 2 control groups of 35 cases). Results: We found that Ptpra -/- mice reproduce neurobehavioral endophenotypes of human SZ: sensitization to methamphetamine-induced hyperactivity, defective sensorimotor gating, and defective habituation to a startle response. Ptpra loss of function also leads to reduced expression of multiple myelination genes, mimicking the hypomyelination-associated changes in gene expression observed in postmortem patient brains. We further report that a polymorphism at the PTPRA locus is genetically associated with SZ, and that PTPRA mRNA levels are reduced in postmortem dorsolateral prefrontal cortex of subjects with SZ. Conclusions: The implication of this well-studied signaling protein in SZ risk and endophenotype manifestation provides novel entry points into the etiopathology of this disease. © 2011 Society of Biological Psychiatry.

DOI： 10.1016/j.biopsych.2011.06.016

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Language：English   Publishing type：Research paper (scientific journal)  

Methamphetamine (MAP) dependence is a highly heritable and aberrant dopaminergic signaling that has been implicated in the disease. Glial cell line-derived neurotrophic factor (GDNF), which plays an important role in the survival of dopaminergic neurons, may be involved in this disorder. In this study, we examined the association between GDNF and MAP dependence using a Japanese population-based sample. We selected eight single nucleotide polymorphisms (SNPs) in the GDNF locus for the association analysis. When patients with MAP dependence were divided into two subgroups consisting of multi-substance and MAP-only users, we detected a significant association between these two groups and the tagging SNP, rs2910704 (after Bonferroni's correction; allele P=0.034). Thus, GDNF is likely to be related to the severity of MAP use in the Japanese population.

DOI： 10.1016/j.pnpbp.2011.04.003

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

There is strong evidence for rare, highly penetrant genetic variants playing an etiological role in multiple neurodevelopmental disabilities, including autism spectrum disorders. The rate of discovery of such rare variants is increasing with the advent of larger sample collections, chromosome microarray analyses, and high-throughput sequencing. As the variants that are being discovered can be highly penetrant, they lead immediately to model systems with construct validity, critical for understanding the underlying neurobiology of these conditions, which in turn can provide leads for novel therapeutic targets. Moreover, these discoveries can benefit families with information about recurrence risk, resolve concerns about etiology, provide information about associated medical issues, and engender directed advocacy for specific genetic conditions. For these reasons, diagnostic laboratories are taking advantage of research data as they are produced. In the current report, we present our molecular analysis of a child with a purported disruptive mutation in SHANK3 identified by a commercial genetic testing laboratory and we provide evidence that this was not an etiological variant. The variant was a 1-bp insertion in exon 11 of the RefSeq gene, which we then determined was inherited from a healthy mother and found in similar to 1% of controls. Since the variant would be predicted to disrupt the reference gene, and the penetrance of SHANK3 mutations is Very high, we did follow up molecular and bioinformatic analyses and concluded that the presumptive exon containing the variant is not likely to be present in most or all SHANK3 transcripts. The results highlight difficulties that can arise with rapid translation of research findings to clinical practice. Researchers are in a unique position to generate resources with collated and curated information that can inform research, genetic testing, clinicians, and families about the best practices as pertains to rare genetic variants in neurodevelopmental disabilities. Of immediate importance would be a well-curated database of gene variation identified in large numbers of typically developing individuals and in individuals affected with neurodevelopmental disabilities. Such a database would reduce false-positive results in clinical settings, would be helpful in structure-function analyses, and would direct translational research to pathways most likely to benefit families. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.brainres.2010.11.005

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PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY-BLACKWELL  

Identifying genes involved in social behavior is important for autism research. Williams-Beuren syndrome (WBS) is a developmental syndrome with unique neurocognitive features, including low IQ deficits in visuospatial and visual-motor abilities, hypersensitivity to sounds, hypersociability, and increased general anxiety. The syndrome is caused by a recurrent hemizygous deletion of the 7q11.23 region, containing about 28 genes. One of genes in the region, GTF2I, has been implicated in the hypersociability and visuospatial deficits of WBS based on genotype-phenotype correlation studies of patients with atypical deletions. In order to clarify the involvement of GTF2I in neurocognitive function, especially social behavior, we have developed and characterized Gtf2i-deficient mice. We found that homozygous deletion of Gtf2i causes lethality during embryonic development with neural tube closure defects and exencephaly, consistent with other reports. Gtf2i heterozygous animals show no gross changes in brain structure or development. Furthermore, heterozygous animals show no alterations in learning and memory, including spatial memory as assessed by the Morris water maze, but show alterations in the recognition of novel objects. Interestingly, they show increased social interaction with unfamiliar mice and do not show typical social habituation processes, reminiscent of the hypersociability observed in WBS patients. The mice do not appear to show increased anxiety, supporting a specific effect of Gtf2i on defined domains of the WBS phenotype. These data indicate that Gtf2i is involved in several aspects of embryonic development and the development of social neurocircuitry and that GTF2I haploinsufficiency could be a contributor to the hypersociability in WBS patients.

DOI： 10.1002/aur.169

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PubMed

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Multiple lines of evidence in schizophrenia, from brain imaging, studies in postmortem brains, and genetic association studies, have implicated oligodendrocyte and myelin dysfunction in this disease. Recent studies suggest that oligodendrocyte and myelin dysfunction leads to changes in synaptic formation and function, which could lead to cognitive dysfunction, a core symptom of schizophrenia. Furthermore, there is accumulating data linking oligodendrocyte and myelin dysfunction with dopamine and glutamate abnormalities, both of which are found in schizophrenia. These findings implicate oligodendrocyte and myelin dysfunction as a primary change in schizophrenia, not only as secondary consequences of the illness or treatment. Strategies targeting oligodendrocyte and myelin abnormalities could therefore provide therapeutic opportunities for patients suffering from schizophrenia. (C) 2010 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.pneurobio.2010.09.004

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PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Background: SHANK3 is a protein in the core of the postsynaptic density (PSD) and has a critical role in recruiting many key functional elements to the PSD and to the synapse, including components of alpha-amino-3-hydroxyl-5-methyl-4-isoxazole-propionic acid (AMPA), metabotropic glutamate (mGlu) and N-methyl-D-aspartic acid (NMDA) glutamate receptors, as well as cytoskeletal elements. Loss of a functional copy of the SHANK3 gene leads to the neurobehavioral manifestations of 22q13 deletion syndrome and/or to autism spectrum disorders. The goal of this study was to examine the effects of haploinsufficiency of full-length Shank3 in mice, focusing on synaptic development, transmission and plasticity, as well as on social behaviors, as a model for understanding SHANK3 haploinsufficiency in humans.
Methods: We used mice with a targeted disruption of Shank3 in which exons coding for the ankyrin repeat domain were deleted and expression of full-length Shank3 was disrupted. We studied synaptic transmission and plasticity by multiple methods, including patch-clamp whole cell recording, two-photon time-lapse imaging and extracellular recordings of field excitatory postsynaptic potentials. We also studied the density of GluR1-immunoreactive puncta in the CA1 stratum radiatum and carried out assessments of social behaviors.
Results: In Shank3 heterozygous mice, there was reduced amplitude of miniature excitatory postsynaptic currents from hippocampal CA1 pyramidal neurons and the input-output (I/O) relationship at Schaffer collateral-CA1 synapses in acute hippocampal slices was significantly depressed; both of these findings indicate a reduction in basal neurotransmission. Studies with specific inhibitors demonstrated that the decrease in basal transmission reflected reduced AMPA receptor-mediated transmission. This was further supported by the observation of reduced numbers of GluR1-immunoreactive puncta in the stratum radiatum. Long-term potentiation (LTP), induced either with.-burst pairing (TBP) or high-frequency stimulation, was impaired in Shank3 heterozygous mice, with no significant change in long-term depression (LTD). In concordance with the LTP results, persistent expansion of spines was observed in control mice after TBP-induced LTP; however, only transient spine expansion was observed in Shank3 heterozygous mice. Male Shank3 heterozygotes displayed less social sniffing and emitted fewer ultrasonic vocalizations during interactions with estrus female mice, as compared to wild-type littermate controls.
Conclusions: We documented specific deficits in synaptic function and plasticity, along with reduced reciprocal social interactions in Shank3 heterozygous mice. Our results are consistent with altered synaptic development and function in Shank3 haploinsufficiency, highlighting the importance of Shank3 in synaptic function and supporting a link between deficits in synapse function and neurodevelopmental disorders. The reduced glutamatergic transmission that we observed in the Shank3 heterozygous mice represents an interesting therapeutic target in Shank3-haploinsufficiency syndromes.

DOI： 10.1186/2040-2392-1-15

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PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Methylenetetrahydrofolate reductase (MTHFR) is a critical molecule for single-carbon transfer reactions. Recent evidence suggests that polymorphisms of MTHFR are related to neural tube deficits and the pathogenesis of schizophrenia. While several studies have demonstrated associations between the gene encoding the MTHFR (MTHFR) polymorphisms and schizophrenia, these studies lack consistency. Therefore, we conducted a gene-wide association study (patients with schizophrenia = 696, control subjects = 747) and performed imputation analysis. Additionally, we performed meta-analysis on currently available data from 18 studies for two common functional polymorphisms (rs1801131 and rs1801133). There were no significant associations with schizophrenia in the single marker analysis for the seven tagging SNPs of MTHFR. In the haplotypic analysis, a nominally significant association was observed between the haplotypes, which included four SNPs (rs1801133, rs17421511, rs17037396, and rs9651118) and the schizophrenic patients. Additionally, the imputation analysis demonstrated there were several associated markers on the MTHFR chromosomal region. However, confirmatory analyses of three tagging SNPs (rs1801133, rs17037396, and rs9651118) and the top SNP (rs17421511) for the imputation results (patients with schizophrenia = 797, control subjects = 1025) failed to replicate the haplotypic analysis and the imputation results. These findings suggest that MTHFR polymorphisms are unlikely to be related to the development of schizophrenia in the Japanese population. However, since our meta-analysis results demonstrated strong support for association of rs1801133 with schizophrenia, further replication studies based on a gene-wide approach need to be considered.

DOI： 10.1016/j.schres.2010.07.011

PubMed

Language：English   Publishing type：Research paper (scientific journal)   Publisher：CELL PRESS  

The prevalence of obesity in children and adults in the United States has increased dramatically over the past decade Genomic copy number variations (CNVs) have been strongly implicated in subjects with extreme obesity and coexisting developmental delay To complement these previous studies, we addressed CNVs in common childhood obesity by examining children with a BMI in the upper 5(th) percentile but excluding any subject greater than three standard deviations from the mean in order to reduce severe cases in the cohort We performed a whole genome CNV survey of our cohort of 1080 defined European American (EA) childhood obesity cases and 2500 lean controls (&lt;50(th) percentile BMI) who were genotyped with 550,000 SNP markers Positive findings were evaluated in an independent African American (AA) cohort of 1479 childhood obesity cases and 1575 lean controls We identified 17 CNV loci that were unique to at least three EA cases and were both previously unreported in the public domain and validated via quantitative PCR Eight of these loci (47 1%) also replicated exclusively in AA cases (six deletions and two duplications) Replicated deletion loci consisted of EDIL3, S1PR5, FOXP2, TBCA ABCB5, and ZPLD1, whereas replicated duplication loci consisted of KIF2B and ARL15 We also observed evidence for a deletion at the 1 PHA6 UNQ6114 locus when the AA cohort was investigated as a discovery set Although these variants may be individually rare our results indicate that CNVs contribute to the genetic susceptibility of common childhood obesity in subjects of both European and African ancestry

DOI： 10.1016/j.ajhg.2010.09.014

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PubMed

Language：English   Publisher：NATL ACAD SCIENCES  

Schizophrenia is a psychiatric disorder with onset in late adolescence and unclear etiology characterized by both positive and negative symptoms, as well as cognitive deficits. To identify copy number variations (CNVs) that increase the risk of schizophrenia, we performed a whole-genome CNV analysis on a cohort of 977 schizophrenia cases and 2,000 healthy adults of European ancestry who were genotyped with 1.7 million probes. Positive findings were evaluated in an independent cohort of 758 schizophrenia cases and 1,485 controls. The Gene Ontology synaptic transmission family of genes was notably enriched for CNVs in the cases (P = 1.5 x 10(-7)). Among these, CACNA1B and DOC2A, both calcium-signaling genes responsible for neuronal excitation, were deleted in 16 cases and duplicated in 10 cases, respectively. In addition, RET and RIT2, both ras-related genes important for neural crest development, were significantly affected by CNVs. RET deletion was exclusive to seven cases, and RIT2 deletions were overrepresented common variant CNVs in the schizophrenia cases. Our results suggest that novel variations involving the processes of synaptic transmission contribute to the genetic susceptibility of schizophrenia.

DOI： 10.1073/pnas.1000274107

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PubMed

Language：English   Publisher：ELSEVIER SCIENCE INC  

Background: SLC25A12, a susceptibility gene for autism spectrum disorders that is mutated in a neurodevelopmental syndrome, encodes a mitochondrial aspartate-glutamate carrier (aspartate-glutamate carrier isoform 1 [AGC1]). AGC1 is an important component of the malate/aspartate shuttle, a crucial system supporting oxidative phosphorylation and adenosine triphosphate production.
Methods: We characterized mice with a disruption of the Slc25a12 gene, followed by confirmatory in vitro studies.
Results: Slc25a12-knockout mice, which showed no AGC1 by immunoblotting, were born normally but displayed delayed development and died around 3 weeks after birth. In postnatal day 13 to 14 knockout brains, the brains were smaller with no obvious alteration in gross structure. However, we found a reduction in myelin basic protein (MBP)-positive fibers, consistent with a previous report. Furthermore, the neocortex of knockout mice contained abnormal neurofilamentous accumulations in neurons, suggesting defective axonal transport and/or neurodegeneration. Slice cultures prepared from knockout mice also showed a myelination defect, and reduction of Slc25a12 in rat primary oligodendrocytes led to a cell-autonomous reduction in MBP expression. Myelin deficits in slice cultures from knockout mice could be reversed by administration of pyruvate, indicating that reduction in AGC1 activity leads to reduced production of aspartate/N-acetylaspartate and/or alterations in the dihydronicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide(+) ratio, resulting in myelin defects.
Conclusions: Our data implicate AGC1 activity in myelination and in neuronal structure and indicate that while loss of AGC1 leads to hypomyelination and neuronal changes, subtle alterations in AGC1 expression could affect brain development, contributing to increased autism susceptibility.

DOI： 10.1016/j.biopsych.2009.08.042

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1111/j.1440-1819.2009.02033.x

PubMed

Language：English   Publisher：BIOMED CENTRAL LTD  

Background: The low-density lipoprotein receptor related protein 1 (LRP1) has been implicated in Alzheimer&apos;s disease (AD) but its signalling has not been fully evaluated. There is good evidence that the cytoplasmic domain of LRP1 is involved in protein-protein interactions, important in the cell biology of LRP1.
Results: We carried out three yeast two-hybrid screens to identify proteins that interact with the cytoplasmic domain of LRP1. The screens included both conventional screens as well as a novel, split-ubiquitin-based screen in which an LRP1 construct was expressed and screened as a transmembrane protein. The split-ubiquitin screen was validated in a screen using full-length amyloid protein precursor (APP), which successfully identified FE65 and FE65L2, as well as novel interactors (Rab3a, Napg, and ubiquitin b). Using both a conventional screen as well as the split-ubiquitin screen, we identified NYGGF4 as a novel LRP1 interactor. The interaction between LRP1 and NYGGF4 was validated using two-hybrid assays, coprecipitation and colocalization in mammalian cells. Mutation analysis demonstrated a specific interaction of NYGGF4 with an NPXY motif that required an intact tyrosine residue. Interestingly, while we confirmed that other LRP1 interactors we identified, including JIP1B and EB-1, were also able to bind to APP, NYGGF4 was unique in that it showed specific binding with LRP1. Expression of NYGGF4 decreased significantly in patients with AD as compared to age-matched controls, and showed decreasing expression with AD disease progression. Examination of Nyggf4 expression in mice with different alleles of the human APOE4 gene showed significant differences in Nyggf4 expression.
Conclusions: These results implicate NYGGF4 as a novel and specific interactor of LRP1. Decreased expression of LRP1 and NYGGF4 over disease, evident with the presence of even moderate numbers of neuritic plaques, suggests that LRP1-NYGGF4 is a system altered early in disease. Genetic and functional studies have implicated both LRP1 and NYGGF4 in obesity and cardiovascular disease and the physical association of these proteins may reflect a common mechanism. This is particularly interesting in light of the dual role of ApoE in both cardiovascular risk and AD. The results support further studies on the functional relationship between NYGGF4 and LRP1.

DOI： 10.1186/1750-1326-5-1

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PubMed

Language：English   Publisher：NATURE PUBLISHING GROUP  

Autism spectrum disorders (ASDs) represent a group of childhood neurodevelopmental and neuropsychiatric disorders characterized by deficits in verbal communication, impairment of social interaction, and restricted and repetitive patterns of interests and behaviour. To identify common genetic risk factors underlying ASDs, here we present the results of genome-wide association studies on a cohort of 780 families (3,101 subjects) with affected children, and a second cohort of 1,204 affected subjects and 6,491 control subjects, all of whom were of European ancestry. Six single nucleotide polymorphisms between cadherin 10 (CDH10) and cadherin 9 (CDH9)-two genes encoding neuronal cell-adhesion molecules-revealed strong association signals, with the most significant SNP being rs4307059 (P = 3.4 x 10(-8), odds ratio = 1.19). These signals were replicated in two independent cohorts, with combined P values ranging from 7.4 x 10(-8) to 2.1 x 10(-10). Our results implicate neuronal cell-adhesion molecules in the pathogenesis of ASDs, and represent, to our knowledge, the first demonstration of genome-wide significant association of common variants with susceptibility to ASDs.

DOI： 10.1038/nature07999

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Language：English   Publisher：FRONTIERS RES FOUND  

Neuronal circuitry relies to a large extent on the presence of functional myelin produced in the brain by oligodendrocytes. Schizophrenia has been proposed to arise partly from altered brain connectivity. Brain imaging and neuropathologic studies have revealed changes in white matter and reduction in myelin content in patients with schizophrenia. In particular, alterations in the directionality and alignment of axons have been documented in schizophrenia. Moreover, the expression levels of several myelin-related genes are decreased in postmortem brains obtained from patients with schizophrenia. These findings have led to the formulation of the oligodendrocyte/myelin dysfunction hypothesis of schizophrenia. In this review, we present a brief overview of the neuropathologic findings obtained on white matter and oligodendrocyte status observed in schizophrenia patients, and relate these changes to the processes of brain maturation and myelination. We also review recent data on oligodendrocyte/myelin genes, and present some recent mouse models of myelin deficiencies. The use of transgenic and mutant animal models offers a unique opportunity to analyze oligodendrocyte and neuronal changes that may have a clinical impact. Lastly, we present some recent morphological findings supporting possible causal involvement of white and grey matter abnormalities, in the aim of determining the morphologic characteristics of the circuits whose alteration leads to the cortical dysfunction that possibly underlies the pathogenesis of schizophrenia.

DOI： 10.3389/neuro.05.009.2009

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Language：English   Publishing type：Research paper (scientific journal)  

NRG1-ERBB signaling influences the risk for schizophrenia pathology. A recent study has reported that MAGI1, MAGI2, and protein tyrosine phosphatase, receptor-type, Z polypeptide 1 (PTPRZ1; located on 7q31.3) gene products regulate the NRG1-ERBB4 signaling pathway, and PTPRZ1 is associated with schizophrenia in a Caucasian population. By applying a gene-based association concept, we analyzed any association between PTPRZ1 tagging SNPs and schizophrenia in the Japanese population (576 schizophrenics and 768 controls). After linkage disequilibrium analysis, 29 single nucleotide polymorphisms (SNPs) were genotyped using a 5'-exonuclease allelic discrimination assay. We found a significant association of one tagging SNP in a genotype-wise analysis (P = 0.007); however, this might be resulted from type I error due to multiple testing (P = 0.17 after SNPSpD correction). No association was observed between schizophrenic patients and controls in either allelic, genotypic, or haplotypic analyses. Our results therefore suggest that PTPRZ1 is unlikely to be related to the development of schizophrenia in the Japanese population.

DOI： 10.1002/ajmg.b.30692

PubMed

Language：English   Publisher：WILEY-LISS  

Abnormalities in neural connections and the neurotransmitter system appear to be involved in the pathophysiology of schizophrenia. The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex, which consists of Syntaxin1A, vesicle-associated membrane protein 2 (VAMP2) and synaptosomal-associated protein 25 kDa (SNAP25), plays an important role in the neurotransmitter system, and is therefore an attractive place to search for candidate genes for schizophrenia. We conducted a two-stage genetic association analysis of Syntaxin1A (STX1A), VAMP2 and SNAP25 genes with schizophrenia (first-set screening samples: 377 cases and 377 controls, second-set confirmation samples: 657 cases and 527 controls). Based on the linkage disequilibrium, 40 SNPs (STX1A, 8 SNPs; VAMP2, 3 SNPs; SNAP25, 29 SNPs) were selected as 'tagging SNPs'. Only nominally significant associations of an SNP (rs12626080) and haplotype (rs363014 and rs12626080) in SNAP25 were detected in the first-set screening scan. To validate this significance, we carried out a replication analysis of these SNP and haplotype associations in second-set samples with a denser set of markers (including five additional SNPs). However, these associations could not be confirmed in the second-set analysis. These results suggest that the SNARE complex-related genes do not play a major role in susceptibility to schizophrenia in the Japanese population. (C) 2008 Wiley-Liss, Inc.

DOI： 10.1002/ajmg.b.30781

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.pnpbp.2008.03.014

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Language：English   Publishing type：Research paper (scientific journal)  

The FXYD domain containing ion transport regulator 6 (FXYD6) gene is located within a region of chromosome 11 (11q23.3) that has been shown by a number of genome scans to be one of the most well-established linkages to schizophrenia. FXYD6 encodes the protein phosphohippolin, which is primarily expressed in the brain. Phosphohippolin modulates the kinetic activity of Na,K-ATPase and has long-term physiological importance in maintaining cation homeostasis. A recent study reported that FXYD6 was associated with schizophrenia in the United Kingdom samples. Applying the gene-based association concept, we carried out an association study regarding FXYD6 and schizophrenia in a Japanese population, with a sample consisting of 2026 subjects (906 schizophrenics and 1120 controls). After linkage disequilibrium analysis, 23 single nucleotide polymorphisms (SNPs) were genotyped using 5'-exonuclease allelic discrimination assay. We found a significant association of two SNPs (rs11216573; genotypic P value: 0.022 and rs555577; genotypic P value: 0.026, allelic P value: 0.011, uncorrected). Nominal P values did not survive correction for multiple testing (rs11216573; genotypic P value: 0.47 and rs555577; genotypic P value: 0.55, allelic P value: 0.24, after SNPSpD correction). No association was observed between schizophrenia patients and controls in allelic, genotypic and haplotypic analyses. Our findings suggest that FXYD6 is unlikely to be related to the development of schizophrenia in a Japanese population.

DOI： 10.1016/j.neulet.2008.04.010

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Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.neulet.2008.01.083

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Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.neulet.2008.02.004

PubMed

Language：English   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Objective Neuroleptic-induced tardive dyskinesia (TD) is an involuntary movement disorder that develops in patients who have undergone long-term treatment with antipsychotic medications, and its etiology is unclear. In this study, a genome-wide association screening was done to identify the pathway(s) in which genetic variations influence susceptibility to neuroleptic-induced TD.
Methods Screening with Sentrix Human-1 Genotyping BeadChip (Illumina, San Diego, California, USA) was done for 50 Japanese schizophrenia patients with treatment-resistant TD and 50 Japanese schizophrenia patients without TD. A total of 40573 single nucleotide polymorphisms that were not in linkage disequilibrium with each other and were located in the exonic and intronic regions of 13 307 genes were analyzed. After gene-based corrections, P values for allelic associations were subjected to canonical pathway-based analyses with Ingenuity Pathway Analysis software (Ingenuity Systems, Inc., Redwood City, California, USA).
Results Eight genes (ABAT, ALDH9A1, GABRA3, GABRA4, GABRB2, GABRAG3, GPHN, and SLC6A11) contained polymorphisms with gene-based corrected allelic P values of less than 0.05. They were aggregated significantly in 33 genes belonging to the gamma-aminobutyric acid (GABA) receptor signaling pathway (P=0.00007, corrected P=0.01). Associations were replicated in an independent sample of 36 patients with TD and 136 patients without TD for polymorphisms in SLC6A11 (GABA transporter 3) (P=0.0004 in the total sample), GABRB2 (beta-2 subunit of GABA-A receptor) (P=0.00007 in the total sample), and GABRG3 (gamma-3 subunit of GABA-A receptor) (P=0.0006 in the total sample).
Conclusion The results suggest that the GABA receptor signaling pathway may be involved in genetic susceptibility to treatment-resistant TD, at least in a subgroup of Japanese patients with schizophrenia. The present results suggest that benzodiazepines may be considered as possible treatment option for TD. Pharmacogenetics and Genomics 18:317-323 (c) 2008 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

DOI： 10.1097/FPC.0b013e3282f70492

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Language：English   Publisher：ELSEVIER SCIENCE BV  

Systematic linkage disequilibrium (LD) mapping of 8p12-21 in the Icelandic population identified neuregulin 1 (NRG1) as a pdrne candidate gene for schizophrenia. However, results of replication studies have been inconsistent, and no large sample analyses have been reported. Therefore, we designed this study with the aim of assessing this putative association between schizophrenia and NRG1 (especially HAP(ICE) region and exon region) using a gene-based association approach in the Japanese population.
This study was a two-stage association analysis with a different panel of samples, in which the significant association found in the first-set screening samples (1126 cases and 1022 controls) was further assessed in the confirmation samples (1262 cases and 1172 controls, and 166 trio samples). In the first-set scan, 60 SNPs (49 tagging SNPs from HapMap database, four SNPs from other papers, and seven SNPs detected in the mutation scan) were examined.
One haplotype showed a significant association in the first-set screening samples (Global P-value= 0.0244, uncorrected). However, we could not replicate this association in the following independent confirmation samples. Moreover, we could not find sufficient evidence for association of the haplotype identified as being significant in the first-set samples by imputing ungenotyped SNPs from HapMap database.
These results indicate that the positionally and functionally attractive regions of NRG1 are unlikely to contribute to susceptibility to schizophrenia in the Japanese population. Moreover, the nature of our results support that two-stage analysis with large sample size is appropriate to examine the susceptibility genes for common diseases. (C) 2008 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.schres.2008.01.010

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.schres.2007.10.028

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Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s10038-007-0142-5

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PubMed

Language：English   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

Several lines of evidence, including diffusion tensor imaging and microarray studies, indicate that abnormalities in myelination play an important role in the pathophysiology of schizophrenia. Of myelin and oligodend rocyte-related genes, a significant decrease in the mRNA levels of transferrin in schizophrenics has been reported by both microarray and quantitative polymerase chain reaction studies. We performed an association analysis of the transferrin gene in a Japanese population of 384 schizophrenic patients and by polymerase chain reaction-restriction fragment length polymorphism and a TaqMan assay. No significant differences in genotype, allele, or haplotype frequencies of the six single nucleotide polymorphisms were observed between schizophrenic patients and controls. The present results suggest that the transferrin gene is not related to the development of schizophrenia in the Japanese population.

DOI： 10.1097/WNR.0b013e3280586890

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Language：English   Publisher：ELSEVIER IRELAND LTD  

It has been suggested that genes involved in the central dopaminergic pathway may contribute to personality traits. However, the results of association studies for these genes have not been consistent. The present study investigated the relationship between the specific polymorphisms of MAO-A, COMT, DRD2, DRD3 and personality traits in Japanese women using a novel genotyping method involving electrochemical DNA array (ECA) chip analysis. Single marker association analysis for each mutation revealed no significant association between scores for Neuroticism Extraversion Openness-Five Factor Inventory (NEO-FFI) items. Gene-gene interaction analysis showed that a MAO-A 30-bp repeat x COMT (Val 158Met) x DRD3 (Ser9Gly) had a marginally significant association with Agreeableness (P=0.0547). The present results suggest that a combination of polymorphisms of MAO-A, COMT, and DRD3 might affect personality traits in Japanese women. (c) 2006 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.neulet.2006.12.018

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Language：Japanese   Publisher：(株)先端医学社  

Neuregulin 1(NRG1)と統合失調症の関連は、Iceland人を対象とした連鎖解析、連鎖不平衡を用いた関連解析で報告されて以来、多くの追試がなされており、統合失調症の疾患感受性遺伝子の中で、最も有望なものの一つである。しかし、追試の結果は必ずしも一致しているわけではなく、有意差を報告する論文もある一方、関連は否定的とする報告もなされている。こうした不一致の原因には多くの要因が考えられるが、本稿では、民族差やサンプル数の問題などを取り上げながら、NRG1の統合失調症との関連を考察していきたい。(著者抄録)