Analysis of CCR5 and SDF‐1 genetic variants and HIV infection in Indian population

HIV‐1 infection and progression exhibits interindividual variation. The polymorphism in the chemokine receptors CCR5 and CXCR4, the principal coreceptors for HIV‐1 and their ligands like SDF‐1 have a profound effect in altering the HIV‐1 disease progression rate. A single nucleotide polymorphism designated SDF1‐3′UTR‐801G‐A has been associated with resistance to HIV‐1 infection or delayed progression to AIDS. In this study, the SDF1‐3′A polymorphism, CCR5?32 polymorphism and CCR5 promoter polymorphism at positions 58934 G/T, 59029 G/A, 59353 T/C, 59356 C/T, 59402 A/G and 59653 C/T were analysed in Indian population. The polymorphisms in HIV‐1 patients and healthy individuals were evaluated by conventional PCR, RFLP‐PCR and direct sequencing techniques. The CCR5?32 mutant allele was found to be almost absent in Indian population. The analysis of the CCR5‐59356C/T polymorphism revealed a trend towards an association of the C allele with an increased risk of HIV‐1 infection. The frequency of allele CCR5‐59356C was higher in HIV‐1 patients (100%) as compared to healthy control subjects (89%, P = 0.003). The correlation of SDF1‐3′A and CCR5 promoter CCR5‐58934G/T, CCR5‐59029G/A, CCR5‐59353T/C, CCR5‐59402 A/G and CCR5‐59653C/T polymorphisms and protection to HIV‐1 infection and progression to AIDS was found to be nonsignificant. Nine haplotypes with more than 1% frequency were detected but were not significant in their protective role against HIV. Comparative analysis with global populations showed a noteworthy difference in CCR5 and SDF‐1 polymorphisms’ frequency distribution, indicating the ethnic variability of Indians. Although susceptibility to infections cannot be completely dependent on one or few genetic variants, it is important to remember that SDF‐1 and CCR5 variants have been correlated globally with HIV‐1 infection and disease progression. In the light of that, higher frequency of SDF‐1 variants in the Indian population is noteworthy.