Abstract
Autism is a largely neurogenetic condition characterized by atypical behaviors, including increased prevalence of motor stereotypies. We used Caenorhabditis elegans to model the T611I variant in the DLG4 ortholog dlg-1 . During phenotyping, we found that some worms intersperse typical dorsoventral swimming bends with left-right bends, resembling an orchestra conductor's arm motions. Conducting behavior occurred in 30% of wild-type but 50% of dlg-1 mutant worms. The high proportion of conducting in dlg-1 is recessive, rescuable with the wild-type gene, and phenocopied with another DLG4 patient variant. This provides an example of autism variants increasing the proportion of a low-penetrant individual behavior.