Allelic association between the NRAMP1 gene and susceptibility to tuberculosis in Guinea-Conakry

Forty four families from Guinea-Conakry were analysed to test for association between NRAMP1 (Natural Resistance Associated Macrophage Protein 1) polymorphisms and tuberculosis. Each family included at least one affected sib and one parent. Healthy sibs were also analysed and on average the families included four members. A total of 160 individuals were included in the final dataset. The analysis of association was performed using an extended TDT test, TRANSMIT, to allow for missing information in the parental genotypes. Three polymorphisms in the NRAMP1 gene were typed: a microsatellite (CB) repeat, a 4 bp deletion in the 3' untranslated region and, a single nucleotide change in intron 4. The single base change in intron 4 was significantly associated (p = 0.036) with tuberculosis. Our results therefore confirm, using a family-based approach on a newly studied population, the previously reported association between this polymorphism and tuberculosis in a population-based study of West Africans.