We identified 327 melanomas (4.6% of the entire melanoma cohort) harboring a missense single nucleotide variant (SNV) mutation in MAP2K1. Of these cases, 221 (3.1% of the melanoma cohort) contained a known or likely pathogenic missense SNV, including E203K (n = 58), P124L (n = 56), P124S (n = 45), D67N (n = 12), C121S (n = 10), F53L (n = 8), Q56P (n = 6), F53Y (n = 6), and K57E (n = 4) (Fig. 2a). Here, MAP2K1 is linked to melanoma.