Although the combination of MM and RCC is not characteristic of known tumor predisposition syndromes (e.g., von Hippel–Lindau, hereditary leiomyomatosis and RCC, Birt–Hogg–Dubé, BAP1 tumor predisposition), a germline mutation in a DNA-repair or tumor-suppressor gene cannot be excluded. The gene discussed is BAP1; the disease is renal cell carcinoma.