Association study of autistic disorder and chromosome 16p.

Autism is a severe neuropsychiatric disorder characterized by social and communicative impairment and repetitive stereotyped behaviors and interest. Although the etiology of autistic disorder (AD) is unknown, a complex genetic component has been strongly implicated. Several screens for AD have recently been completed. Besides seven other chromosomes (1, 2, 4, 7, 10, 19, 22) a region on chromosome 16p between the markers D16S418 (16p13.2) and D16S3114 (16p13.13) shows a significant linkage to AD. The aim of our study was to identify loci associated with the AD in the Italian population using the comparison of polymorphism allele frequency distribution between affected probands and unaffected control subjects. With this aim we have screened six microsatellite markers mapping 16p13.3–16p13.2 for allelic association with AD. A significant association between the marker D16S502 (mapping 16p13.2) and autism has been found. The association is present with the same pattern in two independent samples considered. According to the purpose of our study we believe this association could be useful in directing further mapping efforts of the candidate gene.