Background: Homozygosity (Delta32/Delta32) for the 32 bp deletion in the chemokine receptor 5 (CCR5) gene is associated with strong resistance against HIV infection. Heterozygosity is associated with protection of HIV-1 disease progression.
Methodology/principal findings: We genotyped a population of 737 HIV-positive adults and 463 healthy controls for the CCR5Delta32 deletion and found heterozygous frequencies of 16.2% (HIV-negative) and 17.5% (HIV-positive) among Caucasian individuals. Analysis of CCR5Delta32 influence on disease progression showed notably lower viral setpoints and a longer time to a CD4 count of <200 microl(-1) in seroconverters heterozygous for the deletion. Furthermore, we identified one HIV-positive man homozygous for the Delta32 deletion.
Conclusions/significance: The protective effect of CCR5 Delta32 heterozygosity is confirmed in a large cohort of German seroconverters. The HIV-infected CCR5 Delta32 homozygous individual, however, displays extremely rapid disease progression. This is the 12th case of HIV-infection in this genotype described worldwide.