MC1R and cutaneous mastocytosis: CDKN2A mutation carriers with [R/R, R/r] MC1R genotypes had a statistically significant (p = 0.038) increased OR (6.16) for developing CM compared to CDKN2A mutation carriers with [R/wt, r/r, r/wt, wt/wt] MC1R genotypes, and a statistically significant (p = 0.025) increased risk of developing melanoma 10 years earlier, with an OR of 2.25.