There is wide variation in estimates of risk conferred by carrying a pathogenic CDKN2A mutation, and strong evidence suggests that risk varies across different populations (Bishop et al, 2002), and is influenced by other independent risk factors for melanoma such as level of exposure to ultraviolet radiation (Cannon-Albright et al, 1994; Goldstein et al, 1998), skin pigmentation and freckling (Palmer et al, 2000; van der Velden et al, 2001), and potentially by modifier genes which may, in certain families, also be associated with the presence of atypical nevi (Tucker et al, 1993). Here, CDKN2A is linked to melanoma.