MAP2K1 and melanoma: In contrast to cases with in-frame deletions (Table 2), melanomas with pathogenic missense SNVs in MAP2K1 contained frequent co-mutation in BRAF (58%), NF1 (23%), and NRAS (18%), as well as TERTp (80%), CDKN2A (60%), and TP53 (23%) (Supplemental Fig. 1).