title: New evidence for balancing selection at the HLA-G locus in South Amerindians.
abstract: HLA-G is a non-classical HLA (Human Leukocyte Antigen) molecule characterized by limited tissue distribution under normal physiological conditions and low variability at both DNA and protein levels. Several studies suggest that HLA-G could play a role, as an immunoregulatory molecule, in situations as diverse as transplantation, cancer, viral infections and inflammatory diseases. A total of 237 individuals from 21 South American tribes speaking nine different linguistic families were studied in relation to the 14 bp insertion/deletion polymorphism at the HLA-G gene. A consistent (seven in nine) excess of heterozygosity in samples classified by language was obtained. Our data supply evidences for balancing selection acting at the HLA-G 14 bp INDEL region. Enhanced fetal survival in a pathogen-rich environment may account for these findings.
authors: Departamento de Genética, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. ; Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors: Tiago Degani
authors: TD
authors: Veit
authors: Juciana
authors: J
authors: Cazarolli
authors: Francisco Mauro
authors: FM
authors: Salzano
authors: Marion
authors: M
authors: Schiengold
authors: José Artur Bogo
authors: JA
authors: Chies
keywords: Amerindians; HLA-G 14 bp INDEL; balancing selection; pathogen resistance