Frequencies of KIR genes and KIR genotypes in HIV-exposed seronegative subjects compared with those in low risk controls and HIV-1–infected subjects. Differences between groups are compared by χ² tests or Fisher exact tests when cells have expected counts less than 5. HESN, HIV-exposed seronegative subjects, n = 35; LR, low risk controls, n = 74; HIV, HIV-1–infected controls, n = 68; Cen, centromeric; P values < .05 are shown. (A) Inhibitory KIR genes. (B) Activating KIR genes. (C) KIR2DL2/KIR2DL3 genotypes. (D) Centromeric KIR genotypes.