The MAGEA family is comprised of 12 highly homologous genes clustered at Xq28. The genes are characterized by the presence of a conserved domain (MHD, MAGE Homology Domain). MAGEA gene expression occurs in the normal human germline, and in a wide range of tumors.

MAGEA9 has been reported to be expressed in a variety of tumors, such as hepatobiliary and lung cancers at the mRNA level.

Spontaneous humoral, but not cellular immune responses against MAGEA9 have been detected in cancer patients.

The function of MAGEA9 is unknown.