Finally, epistatic interactions between MHC class I alleles and certain KIR alleles (between KIR3DS1 combined with HLA-B alleles) are associated with slower progression to acquired immunodeficiency syndrome (AIDS) [93] and better resolution of HCV infection (between KIR2DL3 and its human leukocyte antigen C group 1, HLA-C1) [94]. The gene discussed is HLA-B; the disease is AIDS.