The immunohistochemistry has referred positivity in a varying level for the antigens related to the melanoma: NKI/C-3, S-100 protein, gp100 (HMB-45), Mart-1 (Melan-A) (21), vimentin, tyrosinase and microphthalmia transcription factor (MiTF) that are useful in the diagnosis. The gene discussed is PMEL; the disease is melanoma.