Multicohort Genomewide Association Study Reveals a New Signal of Protection Against HIV-1 Acquisition

In the past few years, several genomewide association studies (GWASs) have been conducted to identify host genetic variants involved in control of human immunodeficiency virus type 1 (HIV-1) load and in progression to AIDS [1–10]. Overall, these GWASs emphasized the major role of the HLA chromosome 6 region, particularly the HCP5/HLA-B*57 rs2395029 signal [1–3, 5, 8], and the CXCR6 gene region [7]. These GWASs focused on viral load and disease progression, but genetic correlates of the HIV-1 acquisition phenotype have met limited success: 2 recent GWASs conducted in Malawi reported no significant determinants of HIV infection [11, 12]. Looking for new host factors correlated to HIV susceptibility is critical because the only validated association to date is the 32 base-pair deletion in the CCR5 gene: only 1%–2% of Europeans are homozygous for this mutation and exhibit a near-complete protection against infection by HIV-1 R5 strains [13, 14]. To identify additional genetic factors that might contribute to HIV-1 acquisition, we performed a meta-analysis using GWAS genotypic data from 2 European AIDS progression cohorts, comparing each group of HIV-1–infected patients with uninfected controls of the same ancestry [8, 15]. Next, we replicated the association for the single-nucleotide polymorphism (SNP) showing the smallest P value in the European meta-analysis on 2 independent US cohorts of European ancestry.