There had been no information about epistasis of KIR and MHC class I genes in rhesus macaques compared to respective information in the human KIR/HLA system and HIV-1 infection until a recent study by Albrecht et al. (56) who used 52 SIV-infected rhesus macaques of Indian origin. Here, KIR3DL1 is linked to HIV-1 infection.