A variant of DC-SIGN gene promoter associated with resistance to HIV-1 in serodiscordant couples in Burkina Faso

Objective: To study the involvement of variations in 4 genes associated with susceptibility and/or protection against HIV-1 in serodiscordant couples in Burkina Faso, namely, genes encoding HLA-B57, interferon regulatory factor 1 (IRF1), dendritic cell-specific ICAM3-grabbing nonintegrin (DC-SIGN) and CCR5 delta 32 (CCR5Δ32).

Methods: Two DC-SIGN and two IRF1 single nucleotide polymorphisms (SNPs) as well as HLA-B57*01 and CCR5Δ32 alleles were genotyped in 51 serodiscordant couples in Burkina Faso. DC-SIGN, IRF1 and HLA-B57*01 genotyping was carried out by real time PCR using TaqMan assays (Applied Biosystems, USA and Sacace Biotechnologies, Italy). CCR5Δ32 deletion was investigated by PCR.

Results: The two SNPs of DC-SIGN promoter showed a significant genotypic difference in serodiscordant couples. After multivariate analysis, only the association between DC-SIGN rs2287886 and HIV-1 remained significant (P<0.01). No association was found between IRF1 SNPs and HIV-1 infection. CCR5Δ32 wild type allele was found in 100% of serodiscordant couples. A high frequency of HLA-B57*01 allele was found in the HIV-positive (78%) compared with HIV-negative group (51%), however this difference was no longer significant after the correction of the sex confounding effect in the logistic regression model.

Conclusions: Our study suggests a protective role of a variation of DC-SIGN promoter and genetic resistance to HIV-1 in serodiscordant couples in Burkina Faso.