Notably, our genomic data do not support the presence of any previously known deleterious mutation in any previously identified ASD candidate genes. Although we found no structural or sequence DNA variation in the FOXG1 locus that could explain the increase in FOXG1 gene expression (i.e., a duplication involving the FOXG1 locus or a mutation in a TF binding site in the proximal promoter region), it is possible that uncharacterized SNVs in distal regions could affect FOXG1 expression. Future research may uncover whether the gene expression dysregulation that we identify in these patients with ASD is due to novel mutations in genes that collectively affect the regulatory network of FOXG1.
