In doing so, the melanoma risk locus on chromosome 9 upstream of the MTAP/CDKN2A region reached genome-wide significance (without skin color as a covariate: per-allele odds ratio (OR) = 1.32, P = 3.0 x 10−7; with skin color as a covariate: per-allele OR = 1.42, P = 3.8 x 10−8) (Fig 2). Here, MTAP is linked to melanoma.