SummaryWe present the largest exome sequencing study of autism spectrum disorder (ASD) to date (n=35,584 total samples, 11,986 with ASD). Using an enhanced Bayesian framework to integrate de novo and case-control rare variation, we identify 102 risk genes at a false discovery rate ≤ 0.1. Of these genes, 49 show higher frequencies of disruptive de novo variants in individuals ascertained for severe neurodevelopmental delay, while 53 show higher frequencies in individuals ascertained for ASD; comparing ASD cases with mutations in these groups reveals phenotypic differences. Expressed early in brain development, most of the risk genes have roles in regulation of gene expression or neuronal communication (i.e., mutations effect neurodevelopmental and neurophysiological changes), and 13 fall within loci recurrently hit by copy number variants. In human cortex single-cell gene expression data, expression of risk genes is enriched in both excitatory and inhibitory neuronal lineages, consistent with multiple paths to an excitatory/inhibitory imbalance underlying ASD.

No abstract

Corresponding authors, satterst@broadinstitute.org (FKS) and mjdaly@atgu.mgh.harvard.edu (MJD). Main Text Introductory paragraphAutism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are substantially heritable 1-4 , but individuals with psychiatric diagnoses often do not have blood drawn as part of routine medical procedure, making it difficult to collect large cohorts for genetic study. To overcome this challenge, we drew upon two Danish national resources: the Danish Neonatal Screening Biobank (DNSB) and the Danish national psychiatric registry. We have previously validated the use of archived bloodspots from the DNSB for genotyping 5 and sequencing 6,7 , and we recently performed common variant analysis on dried bloodspot material in both ASD 8 and ADHD 9 . Here, we present exome sequences from over 13,000 DNSB samples, finding that ASD and ADHD show a strikingly similar burden of rare protein-truncating variants, both significantly higher than controls. Additionally, the distributions of genes hit by these variants are not distinguishable between the two disorders, suggesting that many risk genes may be shared between them. These results motivate a combined analysis across ASD and ADHD, which-in conjunction with incorporation of the gnomAD reference database as additional population controls-leads to the identification of genes conferring general risk for childhood psychiatric disorders, including the novel gene MAP1A. Sample overviewExome sequences for individuals included in the iPSYCH research initiative 10 were obtained from archived dried blood samples stored by the DNSB. Individuals in this

Post-traumatic stress disorder (PTSD) is a common and debilitating disorder. The risk of PTSD following trauma is heritable, but robust common variants have yet to be identified by genome-wide association studies (GWAS). We have collected a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls. We first demonstrate significant genetic correlations across 60 PTSD cohorts to evaluate the comparability of these phenotypically heterogeneous studies. In this largest GWAS meta-analysis of PTSD to date we identify a total of 6 genome-wide significant loci, 4 in European and 2 in African-ancestry analyses. Follow-up analyses incorporated local ancestry and sex-specific effects, and functional studies. Along with other novel genes, a non-coding RNA (ncRNA) and a Parkinson's Disease gene, PARK2, were associated with PTSD. Consistent with previous reports, SNP-based heritability estimates for PTSD range between 10-20%. Despite a significant shared liability between PTSD and major depressive disorder, we show evidence that some of our loci may be specific to PTSD. These results demonstrate the role of genetic variation contributing to the biology of differential risk for PTSD and the necessity of expanding GWAS beyond European ancestry.Comparability of PGC2 studies PGC2 compiled the largest collection of global PTSD GWAS to date, with subjects recruited from both clinically deeply characterized, small patient groups and large cohorts with self-reported PTSD symptoms. We did not restrict the type of trauma subjects were exposed to, and trauma included both civilian and/or military events, often with pre-existing exposure to childhood trauma. To evaluate the comparability of these phenotypically heterogeneous studies we first estimated genetic correlations with LDSC, 15 a method that leverages GWAS summary results, the only data type available to PGC-PTSD for several of the larger military and non-US cohorts. We found significant genetic correlations (r g ) between studies using a cross-validation approach including all PGC2 EUA subjects (10 runs with studies randomly placed into 2 groups; mean r g = 0.56, mean SE = 0.23, mean p = 0.029, Supplementary Table 8).Next, additional analyses on the UK Biobank cohort (UKBB) were performed. This cohort comprises a very large proportion of the data, with almost as many EUA cases as the rest of the EUA PGC2 combined (referred to as PGC1.5). PTSD screening in UKBB was based on self-reported symptoms from a mental health survey. 16 We found a considerable genetic correlation between the UKBB and PGC1.5 EUA subjects (r g = 0.73, SE = 0.21, p = 0.0005; Supplementary Table 9). Further, sensitivity analyses in the UKBB using 3 alternative inclusion criteria for PTSD cases and controls showed stable correlations with PGC1.5 (P1 -P3; r g = 0.72 -0.79; Supplementary Table 10). Subsequent analyses were based on the UKBB phenotype including the largest number of subjects (P1; N = 126,188). Sex-stratified genetic correlations support the findings of a significant genetic signal...