Among the 5-10% of melanomas with strong familial linkage or inherited germline defects, mutations in p16 (CDKN2A) [4, 5] and CDK4 [3] are common findings, as is loss of p27 [66, 67] and p16 [68, 69] expression during progression of sporadic melanomas. This evidence concerns the gene CDK4 and melanoma.