Elevated polygenic burden for ASD is associated with the broad autism phenotype

BackgroundAutism spectrum disorder (ASD) is a multifactorial, neurodevelopmental disorder that encompasses a complex and heterogeneous set of traits. Subclinical traits that mirror the core features of ASD, referred to as the broad autism phenotype (BAP) have been documented repeatedly in unaffected relatives and are believed to reflect underlying genetic liability to ASD. The BAP may help inform the etiology of ASD by allowing the stratification of families into more phenotypically and etiologically homogeneous subgroups. This study explored polygenic scores related to the BAP. MethodsPhenotypic and genotypic information were obtained from 2,614 trios from Simons Simplex Sample. Polygenic scores of ASD (ASD-PGS) were generated across the sample to determine the shared genetic overlap between the BAP and ASD. Maternal and Paternal ASD-PGS was explored in relation to BAP traits and their child ASD symptomatology. ResultsMaternal pragmatic language was related to childs social communicative atypicalities. In fathers, rigid personality was related to increased repetitive behaviors in children. Maternal (but not paternal) ASD-PGS was related to the pragmatic language and rigid BAP domains. ConclusionsDomain- and sex-specific associations emerged between parent and child phenotypes. ASD-PGS associations emerged with BAP in mothers only, highlighting the potential for a female protective factor, and implicating the polygenic etiology of ASD-related phenotypes in the BAP.