Repeated divergence of the same genomic region has been found to underlie parallel evolution of pelvic spine reduction in threespine stickleback through repeated deletions within Pitx1 regulatory regions (Chan et al., 2010), and evolution of albinism in Astyanax cavefish has also arisen from independent deletions within the Oca2 locus (Protas et al., 2006). This evidence concerns the gene PITX1 and albinism.