Postoperative pathological staining of the specimen revealed pleomorphic cells and abundant melanin granules (Fig. 1C), whereas immunohistochemical tests demonstrated positive expression of human melanoma black 45 (HMB45), microtubule-associated protein tau 1 (MAPT1), melan A and S100, and negative expression of desmin, synaptophysin, and epithelial membrane antigen (EMA), which was consistent with melanoma. The gene discussed is PMEL; the disease is melanoma.