OXTR and autism spectrum disorder: However, given the limited accessibility to GWAS (mainly due to their cost), and the lack of microarray chips containing the OXTR and AVPR markers reviewed here [for instance, the OXTR SNP rs53576 is not present on many chips currently available for autism spectrum disorders (ASD); Meyer-Lindenberg et al., 2011], selecting a couple of candidate genes and studying their interactions via polygenic association studies remains a valuable approach.