ZNF804A and schizophrenia susceptibility in Asian populations

ZNF804A, a recently identified risk gene for schizophrenia, has been extensively investigated and the principle finding for this locus has been the association with SNP rs1344706 in populations of European ancestries. However, in Asian populations, only a few studies have been conducted for rs1344706 and the results were inconsistent. Here, we studied rs1344706 and schizophrenia susceptibility in multiple Asian case-control samples (10 Chinese and 2 Japanese samples; N?=?21,062), and the meta-analyses indicated non-significant association of rs1344706 with schizophrenia (P?=?0.26), suggesting the same SNP identified in European samples is not predisposing risk in Asians. Further genotyping and association analyses of a set of SNPs spanning the entire genomic region of ZNF804A (520?kb) identified no association except for SNP rs359895 (P?=?7.8?×?10(-5) , N?=?5,172), a newly reported risk SNP located in the ZNF804A promoter region with functional implications. This suggests that ZNF804A may also contribute to schizophrenia susceptibility in Asians although the risk SNP is different from that in Europeans, and it was supported by the detected up-regulation of ZNF804A mRNA expression in the blood cells of Chinese schizophrenia patients compared with normal controls (P?=?0.004). Additionally, the linkage disequilibrium (LD) structure analyses using data from HapMap indicated distinct LD blocks across ZNF804A between Chinese and Europeans, which may explain the different association patterns between them, and also highlight the compounding difficulty of genetic studies of complex diseases like schizophrenia when studying multiple ethnic populations. ? 2012 Wiley Periodicals, Inc.     

Guided motor training induces dendritic spine plastic changes in adult rat cerebellar purkinje cells

Schizophrenia is a complex disorder with a high heritability. Relatives with schizophrenia have an increased risk not only for schizophrenia but also for schizophrenia spectrum disorders, such as schizotypal personality disorder. A single nucleotide polymorphism (SNP), rs1344706, in the Zinc Finger Protein 804A (ZNF804A) gene, has been implicated in susceptibility to schizophrenia by several genome-wide association studies, follow-up association studies and meta-analyses. This SNP has been shown to affect neuronal connectivities and cognitive abilities. We investigated an association between the ZNF804A genotype of rs1344706 and schizotypal personality traits using the Schizotypal Personality Questionnaire (SPQ) in 176 healthy subjects. We also looked for specific associations among ZNF804A polymorphisms and the three factors of schizotypy-cognitive/perceptual, interpersonal and disorganization-assessed by the SPQ. The total score for the SPQ in carriers of the risk T allele was significantly higher than that in individuals with the G/G genotype (p=0.042). For the three factors derived from the SPQ, carriers with the risk T allele showed a higher disorganization factor (p=0.011), but there were no differences in the cognitive/perceptual or interpersonal factors between genotype groups (p>0.30). These results suggest that the genetic variation in ZNF804A might increase susceptibility not only for schizophrenia but also for schizotypal personality traits in healthy subjects.     

首发精神分裂症患者中ZNF804Ars1344706多态性与非典型抗精神病药疗效间的关联分析

目的: 研究首发精神分裂症患者中 ZNF804A 基因rs1344706多态性与非典型抗精神病药疗效间潜在的关系。方法: 71例首发精神分裂症住院患者作为研究对象,随机接受奥氮平、齐拉西酮或阿立哌唑单药治疗4周,所有受试者在基线和治疗结束时均接受1次阳性和阴性症状量表(PANSS)的评定,利用直接测序法确定每位受试者的 ZNF804A rs1344706位点的基因型。结果: 3组不同基因型的首发精神分裂症患者其治疗前后PANSS总分及阳性因子分的变化存在着显著差异(PANSS总分:F=4.608, df=2, P＜0.05;PANSS阳性因子分:F=4.183, df=2, P＜0.05); T携带者的PANSS总分和阳性因子分的改善显著小于G纯合子患者(PANSS总分:F=8.724, df=1, P＜0.01;PANSS阳性因子分:F=9.392, df=1, P＜0.01)。结论: 在首发精神分裂症患者中, ZNF804A rs1344706基因型与非典型抗精神病药物的疗效呈显著相关。     

Polymorphisms of genes involved in inflammation and blood vessel development influence the risk of varicose veins

Heredity plays an important role in the etiology of varicose veins (VVs). However, the genetic basis underlying this condition remains poorly understood. Our aim was to replicate top association signals from genome‐wide association studies (GWASs) for VVs of lower extremities using 2 independent datasets—our sample of ethnic Russian individuals (709 cases and 278 controls) and a large cohort of British residents from UK Biobank (10 861 cases and 397 594 controls). Associations of polymorphisms rs11121615, rs6712038, rs507666, rs966562, rs7111987, rs6062618, and rs6905288 were validated in the UK Biobank individuals at a Bonferroni‐corrected significance level. In Russian cohort, only rs11121615 reached a nominal significance level of P < .05. Results of original GWAS and replication studies were combined by a meta‐analysis, and polymorphisms listed above as well as rs111434909 and rs4463578 passed a genome‐wide significant threshold. Notably, the majority of these polymorphisms were located within or near genes involved in vascular development and remodeling, and regulation of inflammatory response. Our results confirm the role of these polymorphisms in genetic susceptibility to VVs and indicate the revealed genomic regions as good candidates for further fine‐mapping studies and functional analysis. Moreover, our findings implicate inflammation and abnormal vascular architecture in VVs pathogenesis.     

Common variants in DLG1 locus are associated with non‐syndromic cleft lip with or without cleft palate

Non‐syndromic cleft lip with or without cleft palate (nsCL/P) is a common craniofacial anomaly with a complex and heterogeneous aetiology. Knowledge regarding specific genetic factors underlying this birth defect is still not well understood. Therefore, we conducted an independent replication analysis for the top‐associated variants located within the DLG1 locus at chromosome 3q29, which was identified as a novel cleft‐susceptibility locus in our genome‐wide association study (GWAS). Mega‐analysis of the pooled individual data from the GWAS and replication study confirmed that common DLG1 variants are associated with the risk of nsCL/P. Two single nucleotide polymorphisms (SNPs), rs338217 and rs7649443, were statistically significant even at the genome‐wide level (P_trend = 9.70E?10 and P_trend = 8.96E?09, respectively). Three other SNPs, rs9826379, rs6805920 and rs6583202, reached a suggestive genome‐wide significance threshold (P_trend < 1.00E?05). The location of the strongest individual SNP in the intronic sequence of the gene encoding DLG1 antisense RNA suggests that the true causal variant implicated in the risk of nsCL/P may affect the DLG1 gene expression level rather than structure of the encoded protein. In conclusion, we identified a novel cleft‐susceptibility locus at chromosome 3q29 with a DLG1 as a novel candidate gene for this common craniofacial anomaly.     

Dyslexia associated functional variants in Europeans are not associated with dyslexia in Chinese

Genome‐wide association studies (GWAS) of developmental dyslexia (DD) often used European samples and identified only a handful associations with moderate or weak effects. This study aims to identify DD functional variants by integrating the GWAS associations with tissue‐specific functional data and test the variants in a Chinese DD study cohort named READ. We colocalized associations from nine DD related GWAS with expression quantitative trait loci (eQTL) derived from brain tissues and identified two eSNPs rs349045 and rs201605. Both eSNPs had supportive evidence of chromatin interactions observed in human hippocampus tissues and their respective target genes ZNF45 and DNAH9 both had lower expression in brain tissues in schizophrenia patients than controls. In contrast, an eSNP rs4234898 previously identified based on eQTL from the lymphoblastic cell lines of dyslexic children had no chromatin interaction with its target gene SLC2A3 in hippocampus tissues and SLC2A3 expressed higher in the schizophrenia patients than controls. We genotyped the three eSNPs in the READ cohort of 372 cases and 354 controls and discovered only weak associations in rs201605 and rs4234898 with three DD symptoms (p < .05). The lack of associations could be due to low power in READ but could also implicate different etiology of DD in Chinese.     

Genome‐Wide Association Study Confirms SNPs in SNCA and the MAPT Region as Common Risk Factors for Parkinson Disease

Parkinson disease (PD) is a chronic neurodegenerative disorder with a cumulative prevalence of greater than one per thousand. To date three independent genome‐wide association studies (GWAS) have investigated the genetic susceptibility to PD. These studies implicated several genes as PD risk loci with strong, but not genome‐wide significant, associations. In this study, we combined data from two previously published GWAS of Caucasian subjects with our GWAS of 604 cases and 619 controls for a joint analysis with a combined sample size of 1752 cases and 1745 controls. SNPs in SNCA (rs2736990, p‐value = 6.7 × 10^?8; genome‐wide adjusted p = 0.0109, odds ratio (OR) = 1.29 [95% CI: 1.17–1.42] G vs. A allele, population attributable risk percent (PAR%) = 12%) and the MAPT region (rs11012, p‐value = 5.6 × 10^?8; genome‐wide adjusted p = 0.0079, OR = 0.70 [95% CI: 0.62–0.79] T vs. C allele, PAR%= 8%) were genome‐wide significant. No other SNPs were genome‐wide significant in this analysis. This study confirms that SNCA and the MAPT region are major genes whose common variants are influencing risk of PD.     

Replication study of genome‐wide associated SNPs with late‐onset Alzheimer's disease

Late‐onset Alzheimer's disease (LOAD) is a multifactorial disease with the potential involvement of multiple genes. Four recent genome‐wide association studies (GWAS) have found variants showing significant association with LOAD on chromosomes 6, 10, 11, 12, 14, 18, 19, and on the X chromosome. We examined a total of 12 significant SNPs from these studies to determine if the results could be replicated in an independent large case–control sample. We genotyped these 12 SNPs as well the E2/E3/E4 APOE polymorphisms in up to 993 Caucasian Americans with LOAD and up to 976 age‐matched healthy Caucasian Americans. We found no statistically significant associations between the 12 SNPs and the risk of AD. Stratification by APOE*4 carrier status also failed to reveal statistically significant associations. Additional analyses were performed to examine potential associations between the 12 SNPs and age‐at‐onset (AAO) and disease duration among AD cases. Significant associations were observed between AAO and ZNF224/rs3746319 (P = 0.002) and KCNMA1/rs16934131 (P = 0.0066). KCNMA1/rs16934131 also demonstrated statistically significant association with disease duration (P = 0.0002). Although we have been unable to replicate the reported GWAS association with AD risk in our sample, we have identified two new associations with AAO and disease duration that need to be confirmed in additional studies. © 2011 Wiley‐Liss, Inc.     

A case–control genome wide association study of substance use disorder (SUD) identifies novel variants on chromosome 7p14.1 in patients from the United Arab Emirates (UAE)

Genome wide association studies (GWASs) have provided insights into the molecular basis of the disorder in different population. This study presents the first GWAS of substance use disorder (SUD) in patients from the United Arab Emirates (UAE). The aim was to identify genetic association(s) that may provide insights into the molecular basis of the disorder. The GWAS discovery cohort consisted of 512 (250 cases and 262 controls) male participants from the UAE. Controls with no prior history of SUD were available from the Emirates family registry. The replication cohort consisted of 520 (415 cases and 105 controls) Australian male Caucasian participants. The GWAS discovery samples were genotyped for 4.6 million single nucleotide polymorphism (SNP). The replication cohort was genotyped using TaqMan assay. The GWAS association analysis identified three potential SNPs rs118129027 (p‐value = 6.24 × 10^?8), rs74477937 (p‐value = 8.56 × 10^?8) and rs78707086 (p‐value = 8.55 × 10^?8) on ch7p14.1, that did not meet the GWAS significance threshold but were highly suggestive. In the replication cohort, the association of the three top SNPs did not reach statistical significance. In a meta‐analysis of the discovery and the replication cohorts, there were no strengthen evidence for association of the three SNPs. The top identified rs118129027 overlaps with a regulatory factor (enhancer) region that targets three neighboring genes LOC105375237, LOC105375240, and YAE1D1. The YAE1D1, which represents a potential locus that is involved in regulating translation initiation pathway. Novel associations that require further confirmation were identified, suggesting a new insight to the genetic basis of SUD.     

Genome‐wide compound heterozygosity analysis highlighted 4 novel susceptibility loci for congenital heart disease in Chinese population

Genome‐wide association studies (GWASs) have achieved great success in deciphering the genetic cause of congenital heart disease (CHD). However, the heritability of CHD remains to be clarified, and numerous genetic factors responsible for occurrence of CHD are yet unclear. In this study, we performed a genome‐wide search for relaxed forms of compound heterozygosity (CH) in association with CHD using our existing GWAS data including 2265 individuals (957 CHD cases and 1308 controls). CollapsABEL was used to iteratively test the association between the CH genotype and the CHD phenotype in a sliding window manner. We highlighted 17 genetic loci showing suggestive CH‐like associations with CHD (P < 5 × 10^?8), among which 4 genetic loci had expression quantitative trait loci (eQTL) effects in blood (P_eQTL < 0.01). After conditional association analysis, each loci had only 1 independently effective signal reaching the significance threshold (rs2071477/rs3129299 at 6p21.32, P = 2.47 × 10^?10; rs10773097/rs2880921 at 12q24.31, P = 3.30 × 10^?8; rs73032040/rs7259476 at 19q13.11, P = 1.14 × 10^?8; rs10416386/rs4239517 at 19q13.31, P = 1.15 × 10^?9), together explained 7.83% of the CHD variance. Among these 4 associated loci, outstanding candidates for CHD‐associated genes included UBC, CFM2, ZNF302, LYPD3 and CADM4. Although replication studies with larger sample size are warranted, the first CH GWAS of CHD may extend our current knowledge of the genetic contributions to CHD in the Han Chinese population.     

Population‐based identity‐by‐descent mapping combined with exome sequencing to detect rare risk variants for schizophrenia

Genome‐wide association studies (GWASs) are highly effective at identifying common risk variants for schizophrenia. Rare risk variants are also important contributors to schizophrenia etiology but, with the exception of large copy number variants, are difficult to detect with GWAS. Exome and genome sequencing, which have accelerated the study of rare variants, are expensive so alternative methods are needed to aid detection of rare variants. Here we re‐analyze an Irish schizophrenia GWAS dataset (n = 3,473) by performing identity‐by‐descent (IBD) mapping followed by exome sequencing of individuals identified as sharing risk haplotypes to search for rare risk variants in coding regions. We identified 45 rare haplotypes (>1 cM) that were significantly more common in cases than controls. By exome sequencing 105 haplotype carriers, we investigated these haplotypes for functional coding variants that could be tested for association in independent GWAS samples. We identified one rare missense variant in PCNT but did not find statistical support for an association with schizophrenia in a replication analysis. However, IBD mapping can prioritize both individual samples and genomic regions for follow‐up analysis but genome rather than exome sequencing may be more effective at detecting risk variants on rare haplotypes.     

Genome‐wide significant locus for Research Diagnostic Criteria Schizoaffective Disorder Bipolar type

Studies have suggested that Research Diagnostic Criteria for Schizoaffective Disorder Bipolar type (RDC‐SABP) might identify a more genetically homogenous subgroup of bipolar disorder. Aiming to identify loci associated with RDC‐SABP, we have performed a replication study using independent RDC‐SABP cases (n = 144) and controls (n = 6,559), focusing on the 10 loci that reached a p‐value <10^?5 for RDC‐SABP in the Wellcome Trust Case Control Consortium (WTCCC) bipolar disorder sample. Combining the WTCCC and replication datasets by meta‐analysis (combined RDC‐SABP, n = 423, controls, n = 9,494), we observed genome‐wide significant association at one SNP, rs2352974, located within the intron of the gene TRAIP on chromosome 3p21.31 (p‐value, 4.37 × 10^?8). This locus did not reach genome‐wide significance in bipolar disorder or schizophrenia large Psychiatric Genomic Consortium datasets, suggesting that it may represent a relatively specific genetic risk for the bipolar subtype of schizoaffective disorder.     

Genome-wide supported psychosis risk variant in ZNF804A gene and impact on cortico-limbic WM integrity in schizophrenia

Genome-wide association, case association genetic and meta-analytic studies have highlighted ZNF804A as a robust genome-wide supported susceptibility gene for schizophrenia (SCZ). In view of the possible involvement of ZNF804A gene in early neurodevelopment and cellular processes including oligodendrocyte proliferation and differentiation, we examined the effect of ZNF804A on brain WM (WM) integrity in patients with SCZ. Based on extant data in healthy controls (HC), we hypothesized that ZNF804A risk variant rs1344706 is associated with lower fractional anisotropy (FA) in brain regions within cortico-limbic circuits, namely frontal, parietal, medial temporal lobes, and cingulate gyri in SCZ. A total of 200 Chinese participants (125 patients with DSM-IV diagnosis of SCZ and 75 controls) were genotyped using blood samples, a subset of 153 participants (89 patients with DSM-IV diagnosis of SCZ and 64 controls) underwent structural magnetic resonance imaging and diffusion tensor imaging (DTI). There are significant effects of diagnosis (left cingulate gyrus: Adjusted F(1,149) =?9.36, P?=?0.003) and diagnosis-genotype interactions (left parietal lobe: Adjusted F(1,147) =?7.39, P?=?0.007; right parietal lobe: Adjusted F(1,147) =?6.95, P?=?0.009; right medial temporal lobe: Adjusted F(1,147) =?8.79, P?=?0.004; left cingulate gyrus: Adjusted F(1,147) =?8.02, P?=?0.005). Specifically, we found that patients with SCZ who are risk T homozygotes have lower FA in bilateral parietal lobes, and left cingulate gyrus compared with G carriers. Compared with risk T homozygotes in HC, patients with SCZ who are risk T homozygotes have decreased FA in bilateral parietal lobes, and left cingulate gyrus as well as right medial temporal lobe. Our findings suggest that ZNF804A risk variant influence WM integrity involving cortico-limbic brain regions in SCZ and highlight the importance of investigating the impact of genome-wide supported risk factors on intermediate phenotypes with potential to shed light on the neurobiology of SCZ.     

Association of ANK3 with bipolar disorder confirmed in East Asia

Results of genome‐wide association studies (GWASs) for bipolar disorder (BD) have indicated ANK3 as one of the most promising candidates for a susceptibility gene. In this study, we performed genetic association analysis of two single‐nucleotide polymorphisms (SNPs) in ANK3 (rs1938526 and rs10994336), whose genome‐wide significant associations were reported in a previous meta‐analysis of GWASs, using genotyping data of Korean and Japanese case–control samples and a part of data from a GWAS in Han‐Chinese from Taiwan. The total number of participants was 2,212 cases (352 from Korea, 860 from Japan, and 1,000 from Taiwan) and 2,244 controls (349 from Korea, 895 from Japan, and 1,000 from Taiwan). We could not detect any significant difference of allele frequency in individual analyses using each of the three populations. However, when we combined the three data sets and performed a meta‐analysis, rs1938526 showed nominally significant association (P = 0.048, odds ratio = 1.09). The over‐represented allele in BD was same as that reported in Caucasian GWASs. On the other hand, any significant association was not detected in rs10994336. This discrepancy between two SNPs may be explained by the different degree of linkage disequilibrium between Asian and Caucasian. These findings further supported the association between ANK3 and BD, and also suggested the genomic region around rs1938526 as a common risk locus across ethnicities. © 2011 Wiley‐Liss, Inc.     

Genome‐wide analysis of adolescent psychotic‐like experiences shows genetic overlap with psychiatric disorders

This study aimed to test for overlap in genetic influences between psychotic‐like experience traits shown by adolescents in the community, and clinically‐recognized psychiatric disorders in adulthood, specifically schizophrenia, bipolar disorder, and major depression. The full spectra of psychotic‐like experience domains, both in terms of their severity and type (positive, cognitive, and negative), were assessed using self‐ and parent‐ratings in three European community samples aged 15–19 years (Final N incl. siblings = 6,297–10,098). A mega‐genome‐wide association study (mega‐GWAS) for each psychotic‐like experience domain was performed. Single nucleotide polymorphism (SNP)‐heritability of each psychotic‐like experience domain was estimated using genomic‐relatedness‐based restricted maximum‐likelihood (GREML) and linkage disequilibrium‐ (LD‐) score regression. Genetic overlap between specific psychotic‐like experience domains and schizophrenia, bipolar disorder, and major depression was assessed using polygenic risk score (PRS) and LD‐score regression. GREML returned SNP‐heritability estimates of 3–9% for psychotic‐like experience trait domains, with higher estimates for less skewed traits (Anhedonia, Cognitive Disorganization) than for more skewed traits (Paranoia and Hallucinations, Parent‐rated Negative Symptoms). Mega‐GWAS analysis identified one genome‐wide significant association for Anhedonia within IDO2 but which did not replicate in an independent sample. PRS analysis revealed that the schizophrenia PRS significantly predicted all adolescent psychotic‐like experience trait domains (Paranoia and Hallucinations only in non‐zero scorers). The major depression PRS significantly predicted Anhedonia and Parent‐rated Negative Symptoms in adolescence. Psychotic‐like experiences during adolescence in the community show additive genetic effects and partly share genetic influences with clinically‐recognized psychiatric disorders, specifically schizophrenia and major depression.     

Genetic Variation in the Peroxisome Proliferator‐Activated Receptor (PPAR) and Peroxisome Proliferator‐Activated Receptor Gamma Co‐activator 1 (PGC1) Gene Families and Type 2 Diabetes

We used a two‐stage study design to evaluate whether variations in the peroxisome proliferator‐activated receptors (PPAR) and the PPAR gamma co‐activator 1 (PGC1) gene families (PPARA, PPARG, PPARD, PPARGC1A, and PPARGC1B) are associated with type 2 diabetes (T2D) risk. Stage I used data from a genome‐wide association study (GWAS) from Shanghai, China (1019 T2D cases and 1709 controls) and from a meta‐analysis of data from the Asian Genetic Epidemiology Network for T2D (AGEN‐T2D). Criteria for selection of single nucleotide polymorphisms (SNPs) for stage II were: (1) P < 0.05 in single marker analysis in Shanghai GWAS and P < 0.05 in the meta‐analysis or (2) P < 10^?3 in the meta‐analysis alone and (3) minor allele frequency ≥ 0.10. Nine SNPs from the PGC1 family were assessed in stage II (an independent set of middle‐aged men and women from Shanghai with 1700 T2D cases and 1647 controls). One SNP in PPARGC1B, rs251464, was replicated in stage II (OR = 0.87; 95% CI: 0.77–0.99). Gene‐body mass index (BMI) and gene–exercise interactions and T2D risk were evaluated in a combined dataset (Shanghai GWAS and stage II data: 2719 cases and 3356 controls). One SNP in PPARGC1A, rs12640088, had a significant interaction with BMI. No interactions between the PPARGC1B gene and BMI or exercise were observed.     

Genome‐wide significant schizophrenia risk variation on chromosome 10q24 is associated with altered cis‐regulation of BORCS7, AS3MT,and NT5C2 in the human brain

Chromosome 10q24.32‐q24.33 is one of the most robustly supported risk loci to emerge from genome‐wide association studies (GWAS) of schizophrenia. However, extensive linkage disequilibrium makes it difficult to distinguish the actual susceptibility gene(s) at the locus, limiting its value for improving biological understanding of the condition. In the absence of coding changes that can account for the association, risk is likely conferred by altered regulation of one or more genes in the region. We, therefore, used highly sensitive measures of allele‐specific expression to assess cis‐regulatory effects associated with the two best‐supported schizophrenia risk variants (SNP rs11191419 and indel ch10_104957618_I/rs202213518) on the primary positional candidates BORCS7, AS3MT, CNNM2, and NT5C2 in the human brain. Heterozygosity at rs11191419 was associated with increased allelic expression of BORCS7 and AS3MT in the fetal and adult brain, and with reduced allelic expression of NT5C2 in the adult brain. Heterozygosity at ch10_104957618_I was associated with reduced allelic expression of NT5C2 in both the fetal and adult brain. Comparisons between cDNA ratios in heterozygotes and homozygotes for the risk alleles indicated that cis‐effects on NT5C2 expression in the adult dorsolateral prefrontal cortex could be largely accounted for by genotype at these two risk variants. While not excluding effects on other genes in the region, this study implicates altered neural expression of BORCS7, AS3MT, and NT5C2 in susceptibility to schizophrenia arising from genetic variation at the chromosome 10q24 locus. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.

     

Common genetic variation and schizophrenia polygenic risk influence neurocognitive performance in young adulthood

Neurocognitive abilities constitute complex traits with considerable heritability. Impaired neurocognition is typically observed in schizophrenia (SZ), whereas convergent evidence has shown shared genetic determinants between neurocognition and SZ. Here, we report a genome‐wide association study (GWAS) on neuropsychological and oculomotor traits, linked to SZ, in a general population sample of healthy young males (n = 1079). Follow‐up genotyping was performed in an identically phenotyped internal sample (n = 738) and an independent cohort of young males with comparable neuropsychological measures (n = 825). Heritability estimates were determined based on genome‐wide single‐nucleotide polymorphisms (SNPs) and potential regulatory effects on gene expression were assessed in human brain. Correlations with general cognitive ability and SZ risk polygenic scores were tested utilizing meta‐analysis GWAS results by the Cognitive Genomics Consortium (COGENT) and the Psychiatric Genomics Consortium (PGC‐SZ). The GWAS results implicated biologically relevant genetic loci encoding protein targets involved in synaptic neurotransmission, although no robust individual replication was detected and thus additional validation is required. Secondary permutation‐based analysis revealed an excess of strongly associated loci among GWAS top‐ranked signals for verbal working memory (WM) and antisaccade intra‐subject reaction time variability (empirical P < 0.001), suggesting multiple true‐positive single‐SNP associations. Substantial heritability was observed for WM performance. Further, sustained attention/vigilance and WM were suggestively correlated with both COGENT and PGC‐SZ derived polygenic scores. Overall, these results imply that common genetic variation explains some of the variability in neurocognitive functioning among young adults, particularly WM, and provide supportive evidence that increased SZ genetic risk predicts neurocognitive fluctuations in the general population. © 2015 The Authors American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.     

Genome‐wide association study of theta band event‐related oscillations identifies serotonin receptor gene HTR7 influencing risk of alcohol dependence

Event‐related brain oscillations (EROs) represent highly heritable neuroelectrical correlates of human perception and cognitive performance that exhibit marked deficits in patients with various psychiatric disorders. We report the results of the first genome‐wide association study (GWAS) of an ERO endophenotype—frontal theta ERO evoked by visual oddball targets during P300 response in 1,064 unrelated individuals drawn from a study of alcohol dependence. Forty‐two SNPs of the Illumina HumanHap 1 M microarray were selected from the theta ERO GWAS for replication in family‐based samples (N = 1,095), with four markers revealing nominally significant association. The most significant marker from the two‐stage study is rs4907240 located within ARID protein 5A gene (ARID5A) on chromosome 2q11 (unadjusted, Fisher's combined P = 3.68 × 10^?6). However, the most intriguing association to emerge is with rs7916403 in serotonin receptor gene HTR7 on chromosome 10q23 (combined P = 1.53 × 10^?4), implicating the serotonergic system in the neurophysiological underpinnings of theta EROs. Moreover, promising SNPs were tested for association with diagnoses of alcohol dependence (DSM‐IV), revealing a significant relationship with the HTR7 polymorphism among GWAS case–controls (P = 0.008). Significant recessive genetic effects were also detected for alcohol dependence in both case–control and family‐based samples (P = 0.031 and 0.042, respectively), with the HTR7 risk allele corresponding to theta ERO reductions among homozygotes. These results suggest a role of the serotonergic system in the biological basis of alcohol dependence and underscore the utility of analyzing brain oscillations as a powerful approach to understanding complex genetic psychiatric disorders. © 2010 Wiley‐Liss, Inc.