Human melanoma cells express several distinct antigens that are recognized by autologous cytolytic T lymphocytes (CTLs). One class of these antigens is encoded by genes, such as MAGE1 (MAGEA1), MAGE3 (MAGEA3), and BAGE, that are expressed in a large fraction of tumors of various histologic types but are silent in normal adult tissues, except for testis. GAGE1 as a gene encoding an antigen that is present on melanoma MZ2-MEL cells and is recognized by autologous CTLs. The GAGE2 to -6 cDNAs differ mainly by single nucleotide substitutions that are scattered throughout the sequence.

The deduced GAGE5 protein has 117 amino acids. RT-PCR using primers common to GAGE1 to -6 found expression of these genes in various tumors but no expression in any normal adult tissue tested except testis.