Next generation sequencing (NGS) studies have identified many recurrently mutated genes in melanoma, incuding well known genes (PTEN, MAP2K1-2, RB1) and recently identified genes (ARID2, PPP6C, RAC1, DDX3X, IDH1) (23, 24); however, most of these genes are involved in melanoma progression, rather than in melanoma initiation. The gene discussed is RAC1; the disease is melanoma.