Frequency of CCR5 gene 32-basepair deletion in Chilean HIV-1 infected and non-infected individuals

Abstract

A 32-basepair deletion polymorphism in the CCR5 chemokine receptor gene (CCR5Δ32) has been identified and shown to have functional significance in determining susceptibility to infection by human immunodeficiency virus type 1 (HIV-1) and possibly in influencing disease progression in HIV-1 positive individuals. These findings led to an interest in studies of ΔCCR5 allele geographical distribution in human population, for complete understanding of the role of CCR5 in HIV-1 epidemiology. Inter-population variation in CCR5Δ32 frequency may be a significant factor in the prediction of AIDS endemicity. In this report we assessed the frequency of ΔCCR5 in a Chilean population (63 HIV-1 infected and 62 non-infected individuals). No homozygous CCR5Δ32 individual was identified, and no significant difference was observed between HIV-1 infected (3/63) and non-infected (3/62) individuals for the heterozygote CCR5Δ32 state. This is the first evidence of the contribution of ΔCCR5 allele to the genetic background of the Chilean population, which is characterized by intense ethnic admixture and by gene flow from the European Spanish gene pool.