Members of the BAGE gene family encode antigens that are recognized by cytotoxic T lymphocytes and are also known as CT (cancer/testis) antigens. Generated by juxtacentromeric shuffling of the MLL3 gene, the ancestral BAGE gene was expanded by acrocentric exchanges and/or juxtacentromeric movements. BAGE, also known as B melanoma antigen 1 or cancer/testis antigen 2.1, is a 43 amino acid member of the BAGE family. Generally, BAGE proteins are not expressed in normal tissues, except in testis, but are expressed highly in melanomas, bladder carcinomas, head and neck squamous cell carcinomas, and lung and breast cancer carcinomas. BAGE proteins are not expressed in renal, colorectal and prostatic carcinomas, leukemias and lymphomas.