DEFB1 polymorphisms and HIV-1 mother-to-child transmission in Zambian population

Abstract

Introduction: Human Beta Defensin-1 (hBD-1) is a component of the innate immune system, the first line of defence against pathogens, already reported as involved in the susceptibility to HIV-1 infection and HIV-1 mother-to-child transmission (MTCT) in different populations. We investigated the role of DEFB1 gene (encoding for hBD-1) functional polymorphisms in the susceptibility to HIV-1 MTCT in a population from Zambia.

Methods: Four selected polymorphisms within DEFB1 gene, three at the 5′ untranslated region (UTR), namely -52G > A (rs1799946), -44C > G (rs1800972) and -20G > A (rs11362) and one in the 3′UTR, c.*87A > G (rs1800972), were genotyped in 101 HIV-1 positive mothers (26 transmitters -27% and 75 not transmitters -73%) and 331 infants born to HIV-1 infected mothers (85 HIV-1 positive -26% and 246 exposed but not infected -74%).

Results: DEFB1 c.*87–A allele was more frequent among HIV− children with respect to HIV+ (with intrauterine MTCT). Concerning DEFB1 haplotypes, GCGA haplotype resulted more represented in HIV− than HIV+ infants and DEFB1 ACGG haplotype presented increased frequency in HIV− children respect to HIV+ (with intra-partum MTCT) (p = .02, p = .002 and p = .006, respectively).

Conclusions: DEFB1 polymorphisms were significantly associated with decreased risk of HIV-1 infection acquisition in the studied Zambian population suggesting that they may play a role in HIV-1 MTCT.

Keywords:

• DEFB1
• haplotypes
• HIV-1
• innate immunity
• polymorphisms

Disclosure statement

The authors declared no conflict of interest.

Additional information

Funding

This work has been supported by [RC08/17] grant from IRCCS Burlo Garofolo Trieste/Ministry of Health (Italy). This study was supported in part by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health (NIH) [HD39611, HD40777, HD57617]. VP was recipient of fellowship from IRCCS Burlo Garofolo.