Essential myoclonus in a kindred with familial malignant melanoma

We studied a kindred in which three members had essential myoclonus and seven members had malignant melanoma. Two of the persons with myoclonus had melanoma and the third carried the genetic predisposition for melanoma. The coexistence of the two disorders in these patients could represent coincidence, linkage between the two dominant genes, or the pleiotropic expression of a single gene affecting neuroectodermal derivatives.