Author(s): Freitas, Tamira ; Brehm, António ; Fernandes, Ana Teresa
Date: 2006
Persistent ID: http://hdl.handle.net/10400.13/3016
Origin: DigitUMa - Repositório da Universidade da Madeira
Subject(s): DS: CCR5 polymorphism; Atlantic islands; Madeira (Portugal); Azores (Portugal); Cabo Verde; São Tomé e Princípe; HIV infection; .; Faculdade de Ciências da Vida
There is evidence thathe CCR5-A32 mutation confers protection against HIV-1 infection tohomozygous 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 (-10%). We carried out the present study to determine the 32-bp deletion allele and genotype frequencies of the CCR5 gene (CCR5-A32 ) in the Atlantic island populations of Madeira, the Azores, Cabo Verde, and Säo 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-A32 mutation varies between 0% in Säo Tomé e Principe 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 Säo Tomé e Principe and Cabo Verde, and even within populations (e.g., Portugal, Madeira, and the Azores).
