Protective Effect of the Combination of Wild-Type Genotypes (G/G and G/G) of CCR2-64V and SDF1-3A' Genes in Serodiscordant Couples in Yaounde-Cameroon

Background: There is growing evidence that polymorphisms in chemokine and chemokine receptor genes influence susceptibility to HIV infection and disease progression. However, not much is documented about the influence of these polymorphisms in HIV serodiscordant couples in Cameroon.

Objective: The objective of this study therefore was to determine the prevalence and the effect of the polymorphisms of CCR5-Δ32, CCR5 promoter 59029 A/G, CCR2-64I and SDF1-3'A gene in HIV serodiscordant couples in comparison to HIV negative seroconcordant and HIV positive seroconcordant couples in Yaoundé-Cameroon.

Methods: A total of 96 couples were recruited from five hospitals, of which 60 couples were HIV serodiscordant (test group), 18 HIV negative seroconcordant and 18 HIV positive seroconcordant couples were used as controls. Their genotypes for CCR5-Δ32, CCR5 promoter, CCR2 and SDF1 were analyzed using polymerase chain reaction (PCR) and restriction fragment length polymorphism.

Results: The allelic frequencies of these genes in the studied population were: 0%, 26.30%, 15.30% and 1.62% respectively for CCR5-Δ32, CCR5 promoter, CCR2 and SDF1. The frequency of the combination of CCR5 promoter and SDF1- (A/A+ G/G) wild-type genotype was higher in HIV-infected partners (82.92%) compared to uninfected partners (56.1%) in HIV serodiscordant couples (p= 0.0001). The combination of wild-type CCR2 and SDF1 genotypes (G/G + G/G) was higher among uninfected partners (80.48%) in HIV serodiscordant couples compared to the infected partners (60.97) (p= 0.005).

Conclusion: HIV negative partner protection against HIV/AIDS infection may be attributed to the combination of wild-type genotypes (G/G and G/G) of CCR2 and SDF1 genes in HIV serodiscordant couples.