Recessive gene disruptions in autism spectrum disorder

Autism spectrum disorder (ASD) affects up to 1 in 59 individuals(1). Genome-wide association and large-scale sequencing studies strongly implicate both common variants(2–4) and rare de novo variants(5–10) in ASD. Recessive mutations have also been implicated(11–14) but their contribution remains less well defined. Here we demonstrate an excess of biallelic loss-of-function and damaging missense mutations in a large ASD cohort, corresponding to ~5% of total cases, including 10% of females, consistent with a female protective effect. We document biallelic disruption of known or emerging recessive neurodevelopmental genes (CA2, DDHD1, NSUN2, PAH, RARB, ROGDI, SLC1A1, USH2A) as well as other genes not previously implicated in ASD including the transcription factor FEV, a key regulator of the serotonergic circuitry. Our data refine estimates of the contribution of recessive mutation to ASD and suggest new paths for illuminating novel biological pathways responsible for this condition.