Uncontrolled cell-cycle progression is a hallmark characteristic of melanoma development, and multiple components in this process are found to be mutated, including cyclin-dependent kinase inhibitor 2A (CDKN2A), retinoblastoma-associated protein (RB), Cyclin D1, and cyclin-dependent kinase 4/6 (CDK4/6). This evidence concerns the gene CDKN2A and melanoma.