CD4 and AIDS: Subjects in group 5 (heterozygosity for the HLA-A10/ZNRD1-C-containing haplotype) were also similar to those in group 1 with respect to most of these laboratory and immunologic characteristics, except those in group 5 had lower cumulative CD4+ T cell counts, a parameter that reflects the amount of CD4+ T cell loss over disease course and is a parameter that is highly correlated with development of AIDS ([39]; Figure 2E).