par Libert, Frédérick ;Cochaux, Pascale ;Beckman, G;Samson, M;Aksenova, M;Cao, A;Czeizel, A;Claustres, M;de la Rúa, C;Ferrari, M.;Ferrec, C;Glover, G;Grinde, B;Güran, S;Kucinskas, V;Lavinha, J;Mercier, B;Ogur, M. Gonul ;Peltonen, Leena;Rosatelli, C;Schwartz, M.;Spitsyn, V;Timar, L;Beckman, L;Parmentier, Marc ;Vassart, Gilbert
Référence Human molecular genetics, 7, 3, page (399-406)
Publication Publié, 1998-03
Référence Human molecular genetics, 7, 3, page (399-406)
Publication Publié, 1998-03
Article révisé par les pairs
Résumé : | The chemokine receptor CCR5 is encoded by the CMKBR5 gene located on the p21.3 region of human chromosome 3, and constitutes the major co-receptor for the macrophage-tropic strains of HIV-1. A mutant allele of the CCR5 gene, Delta ccr5 , was shown to provide to homozygotes with a strong resistance against infection by HIV. The frequency of the Delta ccr5 allele was investigated in 18 European populations. A North to South gradient was found, with the highest allele frequencies in Finnish and Mordvinian populations (16%), and the lowest in Sardinia (4%). Highly polymorphic microsatellites (IRI3.1, D3S4579 and IRI3.2, D3S4580 ) located respectively 11 kb upstream and 68 kb downstream of the CCR5 gene deletion were used to determine the haplotype of the chromosomes carrying the Delta ccr5 variant. A strong linkage disequilibrium was found between Delta ccr5 and specific alleles of the IRI3.1 and IRI3.2 microsatellites: >95% of the Delta ccr5 chromosomes carried the IRI3.1-0 allele, while 88% carried the IRI3.2-0 allele. These alleles were found respectively in only 2 or 1.5% of the chromosomes carrying a wild-type CCR5 gene. From these data, it was inferred that most, if not all Delta ccr5 alleles originate from a single mutation event, and that this mutation event probably took place a few thousand years ago in Northeastern Europe. The high frequency of the Delta ccr5 allele in Caucasian populations cannot be explained easily by random genetic drift, suggesting that a selection advantage is or has been associated with homo- or heterozygous carriers of the Delta ccr5 allele. |