Two major alterations reported in melanoma for this pathway are inactivation of p16CDKN2A and amplification of CCND1: the first alteration is due to genetic (gene mutations, chromosomal rearrangements) or epigenetic (methylation of promoter regions) mechanisms, while the second one mainly occurs in melanomas negative for mutations in BRAF and NRAS genes (1, 13). The gene discussed is CCND1; the disease is melanoma.