HLA-B and HIV-1 infection: An explorative multiple correspondence analysis of selected chromosome 6 polymorphisms within the HLA-B and -C class I region and of KIR genes was conducted independently to verify whether combinations of the selected chromosome 6 and 19 markers could discriminate between the two best characterized cohorts of natural controller of HIV-1 infection, i.e. EC and LTNP, in comparison to HIV-1 Progressors (P) or HIV-1 seronegative healthy blood donors (HD).