title: Frequency of the CCR5-delta32 mutation in the Atlantic island populations of Madeira, the Azores, Cabo Verde, and São Tomé e Príncipe.
abstract: There is evidence that the CCR5-delta32 mutation confers protection against HIV-1 infection to homozygous individuals. It is believed that this mutation spread through Europe with the Vikings and that it has been subjected to positive selection, leading to a high frequency in Europe (approximately 10%). We carried out the present study to determine the 32-bp deletion allele and genotype frequencies of the CCR5 gene (CCR5-delta32) in the Atlantic island populations of Madeira, the Azores, Cabo Verde, and São Tomé e Principe. These Atlantic archipelagos were all colonized by the Portuguese in the 15th and 16th centuries, but the latter two received most of their settlers from the West African coast. The frequency of the CCR5-delta32 mutation varies between 0% in São Tomé e Príncipe and 16.5% in the Azores. The Azores Islands have one of the highest frequencies of homozygotes found in Europe (4.8%). There are significant differences (P < 0.05) between some of these populations, for example, between São Tomé e Príncipe and Cabo Verde, and even within populations (e.g., Portugal, Madeira, and the Azores).
authors.affiliation: Human Genetics Laboratory, University of Madeira, 9000-390 Funchal, Portugal.
authors.forename: Tamira
authors.initials: T
authors.lastname: Freitas
authors.forename: António
authors.initials: A
authors.lastname: Brehm
authors.forename: Ana Teresa
authors.initials: AT
authors.lastname: Fernandes
mesh_terms: D001266:Atlantic Islands; D001394:Azores; D044383:Black People / Q000235:genetics; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D018703:Founder Effect; D017353:Gene Deletion; D005787:Gene Frequency; D005828:Genetics, Population; D005838:Genotype; D015497:HIV-1 / Q000235:genetics*; D006239:Haplotypes; D006801:Humans; D011110:Polymorphism, Genetic / Q000235:genetics*; D011174:Portugal; D019713:Receptors, CCR5 / Q000235:genetics*; D044465:White People / Q000235:genetics
chemical_list: D019713:Receptors, CCR5