The tests of transgenerational epistasis, particularly the “Difference” model, also identified many genes previously implicated in autism at the suggestive P<10−4 level, such as MACROD2, RORA, SDK1, GABRB3, PCDH9, NRXN1, RELN, FHIT, CNTN4 and LAMA1[8], [36], [37], [43], [47], [48], [49], [50], [51], [52]. This evidence concerns the gene PCDH9 and autism.