In summary, our analysis of CCR2-CCR5 haplotypes consisting of common combinations of SNP alleles spanning those two genes has confirmed a previously reported association of haplotype HHF*2 with favorable response to HIV-1 infection; and our longitudinal analysis of seroconversion in HESN African heterosexual partners has detected probable contributions by the HHD/HHE diplotype to acquisition of infection [11,17,39]. The gene discussed is CCR5; the disease is HIV-1 infection.