CDKN2A and melanoma: Another key element underscoring the multifactorial nature of melanoma is that, among families with CDKN2A mutations, family members harboring wild-type (wt) CDKN2A (i.e., phenocopies) tend to develop melanomas at a younger age compared to individuals with sporadic melanoma, even though the frequency of multiple primary melanomas in wt relatives still remains much lower compared to that of CDKN2A mutation carriers [29].