Mamu-A*01 is a rhesus macaque (Macaca mulatta) MHC (major histocompatibility complex) class I allele which can present a peptide from the SIV (simian immunodeficiency virus) gag protein for stimulating CTLs (cytotoxic T lymphocytes). Expression of Mamu-A*01 is significantly associated with lower viral load and longer survival time in SIV infected rhesus macaques. Mamu-A*01 positive rhesus macaques infected with SIV are therefore often used as an AIDS model for pathogenesis study and vaccine evaluation. The frequency of Mamu-A*01 allele detected in Indian rhesus macaques is from 22.06 to 66.16%, while in Chinese rhesus macaques is from 0 to 3.85%.