Melanoma-associated antigen (MAGE) are completely silent in normal tissues, with the exception of male germ cells, and, for some of them, placenta. These antigens ought to be strictly tumor specific, expressed in tumor cells of various histological types. Because of their specific expression on tumor cells, these antigens are of particular interest for antitumor immunotherapy. Genes of the MAGE family direct the expression of tumor antigens that are recognized on a human melanoma by autologous cytolytic T lymphocytes. Though the function of MAGE is unknown, may play a role in embryonal development and tumor transformation or aspects of tumor progression.