CDK4 and melanoma: We detected clonal mutations of all types that affected genes known to contribute to melanoma initiation, including hotspot SNVs in Kras and Gnaq, SNVs in frequently mutated sites of Sf3b1 and Tfap2a, homozygous deletion of Cdkn2a, and amplifications of Met, Braf, Mitf, Kras, Cdk4, and Erbb3.