The MEK and BRafV600E melanomas were indistinguishable from each other and from the melanomas arising in Dct::TVA;BrafCA;Cdkn2alox/lox;Ptenlox/lox mice36 infected with Cre, as we have previously reported.35 As with Dct::TVA NRasQ61R33 and BRafCA 4 tumors, all of the melanomas arising in this study were highly invasive and consisted primarily of short spindle cells exhibiting high-grade nuclear features and prominent nucleoli (Figure 6a). This evidence concerns the gene MAP2K7 and melanoma.