[Familial malignant melanoma].

Patients with familial malignant melanoma(FMM) are susceptible for melanoma and multiple dysplastic nevi(atypical mole). FMM is also called as dysplastic nevus syndrome or familial atypical mole and melanoma syndrome. The number of Japanese patients with FMM is very low. In 1994, p16(MTS1, INK4A, CDK4I, CDKN2) gene was cloned as the gene for FMM. p16 gene locus also codes for p14ARF and acts as tumor suppressor through activation of Rb by p16 and p53 by p14ARF. Approximately 20% of FMM patients were shown to carry the germline mutations of p16, indicating the presence of another gene or other genes for FMM, which also may be involved in the development of sporadic malignant melanoma.