UC Irvine

Autism is a complex and both genetically and phenotypically heterogeneous neurodevelopmental condition. Some clear genetic causes have been identified but for most cases of autism the cause is unknown. Previous studies attempting to fill in some of this gap in understanding have suggested a link between autism and variants in genes related to epigenetic control of gene expression including those involved in methylation and chromatin modification. We analyzed whole exome sequencing data for seven families and probands with autism for novel, rare, and common protein damaging variants and found 22 variants in 20 genes related to methylation, acetylation, and chromatin remodeling. Our analysis also revealed a burden of eight inherited variants in the one-carbon metabolism pathway in an autistic proband. These findings suggest that both defects in enzymes related to epigenetic regulation and the interactions of multiple related variants may each provide insight into the pathophysiology of autism.