SF3B1 mutations have an incidence of approximately 20% in UM [20,25,26], 42% in mucosal melanoma (60% in anorectal melanoma and 44% in vulvovaginal melanoma) [36], 7% in MDS (80% in refractory anemia with ring sideroblasts (RARS)-MDS, a subset of MDS) [31], 10% in CLL [32] and approximately 1.8% in breast cancer [37]. This evidence concerns the gene SF3B1 and mucosal melanoma.