Notably, mutations in KRAS were in hotspot codons 12 and 61 and mutually exclusive from other mutations in the mitogen-activated protein kinase (MAPK) signalling genes including BRAFV600, NRAS and HRAS, and this pattern of mutually exclusivity was also observed in KRAS-mutant melanomas within the SKCM-TCGA and SKCM-MSK datasets (Fig. 1b and Supplementary Table 6). This evidence concerns the gene HRAS and melanoma.