SHANK3 and autism: All other mammals in the UCSC Genome Browser are listed as monomorphic for the C allele, except squirrel monkeys that are monomorphic for T. Given the associations of SHANK3 with PMS and the effects on speech and language in PMS, we predicted that the SHANK3 rs9616915 SNP would affect nonclinical autism or schizotypal phenotypes relevant to PMS, in particular the subscale traits associated with speech and language.