Recurrent de novo (DN) and likely gene-disruptive (LGD) mutations contribute significantly to autism spectrum disorders (ASDs) but have been primarily investigated in European cohorts. Here, we sequence 189 risk genes in 1,543 Chinese ASD probands (1,045 from trios). We report an 11-fold increase in the odds of DN LGD mutations compared with expectation under an exome-wide neutral model of mutation. In aggregate, ∼4% of ASD patients carry a DN mutation in one of just 29 autism risk genes. The most prevalent gene for recurrent DN mutations is SCN2A (1.1% of patients) followed by CHD8, DSCAM, MECP2, POGZ, WDFY3 and ASH1L. We identify novel DN LGD recurrences (GIGYF2, MYT1L, CUL3, DOCK8 and ZNF292) and DN mutations in previous ASD candidates (ARHGAP32, NCOR1, PHIP, STXBP1, CDKL5 and SHANK1). Phenotypic follow-up confirms potential subtypes and highlights how large global cohorts might be leveraged to prove the pathogenic significance of individually rare mutations.

This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder (ASD) in Chinese children. We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling. The Modified Chinese Autism Spectrum Rating Scale was used for the screening process. Of the target population of 142,086 children, 88.5% (n = 125,806) participated in the study. A total of 363 children were confirmed as having ASD. The observed ASD prevalence rate was 0.29% (95% CI: 0.26%-0.32%) for the overall population. After adjustment for response rates, the estimated number of ASD cases was 867 in the target population sample, thereby achieving an estimated prevalence of 0.70% (95% CI: 0.64%-0.74%). The prevalence was significantly higher in boys than in girls (0.95%; 95% CI: 0.87%-1.02% versus 0.30%; 95% CI: 0.26%-0.34%; P \ 0.001). Of the 363 confirmed ASD cases, 43.3% were newly diagnosed, and most of those (90.4%) were attending regular schools, and 68.8% of the Hao Zhou, Xiu Xu, Weili Yan contributed equally.Members of the LATENT-NHC Study Team are listed in the Supplementary Materials.

BackgroundWe previously performed targeted sequencing of autism risk genes in probands from the Autism Clinical and Genetic Resources in China (ACGC) (phase I). Here, we expand this analysis to a larger cohort of patients (ACGC phase II) to better understand the prevalence, inheritance, and genotype–phenotype correlations of likely gene-disrupting (LGD) mutations for autism candidate genes originally identified in cohorts of European descent.MethodsWe sequenced 187 autism candidate genes in an additional 784 probands and 85 genes in 599 probands using single-molecule molecular inversion probes. We tested the inheritance of potentially pathogenic mutations, performed a meta-analysis of phase I and phase II data and combined our results with existing exome sequence data to investigate the phenotypes of carrier parents and patients with multiple hits in different autism risk genes.ResultsWe validated recurrent, LGD, de novo mutations (DNMs) in 13 genes. We identified a potential novel risk gene (ZNF292), one novel gene with recurrent LGD DNMs (RALGAPB), as well as genes associated with macrocephaly (GIGYF2 and WDFY3). We identified the transmission of private LGD mutations in genes predominantly associated with DNMs and showed that parental carriers tended to share milder autism-related phenotypes. Patients that carried DNMs in two or more candidate genes show more severe phenotypes.ConclusionsWe identify new risk genes and transmission of deleterious mutations in genes primarily associated with DNMs. The fact that parental carriers show milder phenotypes and patients with multiple hits are more severe supports a multifactorial model of risk.Electronic supplementary materialThe online version of this article (10.1186/s13229-018-0247-z) contains supplementary material, which is available to authorized users.

Most genes associated with neurodevelopmental disorders (NDDs) were identified with an excess of de novo mutations (DNMs) but the significance in case–control mutation burden analysis is unestablished. Here, we sequence 63 genes in 16,294 NDD cases and an additional 62 genes in 6,211 NDD cases. By combining these with published data, we assess a total of 125 genes in over 16,000 NDD cases and compare the mutation burden to nonpsychiatric controls from ExAC. We identify 48 genes (25 newly reported) showing significant burden of ultra-rare (MAF < 0.01%) gene-disruptive mutations (FDR 5%), six of which reach family-wise error rate (FWER) significance (p < 1.25E−06). Among these 125 targeted genes, we also reevaluate DNM excess in 17,426 NDD trios with 6,499 new autism trios. We identify 90 genes enriched for DNMs (FDR 5%; e.g., GABRG2 and UIMC1); of which, 61 reach FWER significance (p < 3.64E−07; e.g., CASZ1). In addition to doubling the number of patients for many NDD risk genes, we present phenotype–genotype correlations for seven risk genes (CTCF, HNRNPU, KCNQ3, ZBTB18, TCF12, SPEN, and LEO1) based on this large-scale targeted sequencing effort.

Schizophrenia and autism spectrum disorder (ASD) are significant public health problems. Scientists have recently explored the association between schizophrenia and ASD, but the findings are inconsistent. Thus, we conducted a systematic review and meta-analysis of epidemiological studies to examine the association between schizophrenia and ASD. PubMed, Embase, and the Cochrane Library were used for literature searches to identify eligible studies published in English before October 2, 2017. Relevant studies estimating the association between schizophrenia and ASD were included. The meta-analysis of the prevalence of schizophrenia in individuals with ASD encompassed 1,950,113 participants and 14,945 individuals with ASD. A random-effects model was chosen to synthesize the effect sizes of individual studies. The prevalence of schizophrenia was significantly higher in individuals with ASD than in controls (odds ratio = 3.55, 95% confidence interval: 2.08-6.05, P < .001). Both sensitivity analysis and publication bias testing revealed that the findings were robust. The systematic review of the prevalence of ASD in individuals with schizophrenia encompassed 930 participants. The prevalence of ASD in individuals with schizophrenia ranged from 3.4 to 52%. The systematic review and meta-analysis showed a significant association between schizophrenia and ASD.Lay Summary: This systematic review and meta-analysis explored the association between schizophrenia and ASD. We found that the prevalence of schizophrenia was significantly higher in individuals with ASD than in controls and the prevalence of ASD in individuals with schizophrenia ranged from 3.4 to 52%. A comprehensive estimation of schizophrenia and ASD has important implications for the diagnosis, treatment, prognosis, and development of a fundamental understanding of these disorders.