title: Distribution of GSTM1, GSTT1, GSTP1 and TP53 disease-associated gene variants in native and urban Venezuelan populations.
abstract: The contemporary Venezuelan population is the product of major admixture process across various historical events, which has provided it a particular genetic background. The aim of this study concerns the analysis of glutathione S-transferase (GST) GSTM1, GSTP1 and GSTT1 genetic variants and five polymorphisms at the TP53 gene, which are related to cancer susceptibility, in an urban/admixed population and five Amerindian tribes (Bari, Panare, Pemon, Warao and Wayuu) from Venezuela. Genotyping was carried out in 120 individuals from an urban sample and 188 Amerindians. The analysis performed on TP53 haplotype and GST allele distribution showed a close correlation for Pemon and Warao populations, while Bari group appears isolated from the other populations. GSTT1 null variant frequency in our admixed (11%) and native samples (0.0-11.4%) was lower when compared with Caucasians, Africans and Asians. Frequency of the GSTP1*Val cancer-associated allele found in Bari (88.6%) and Panare (63.0%) is of the highest so far reported. Fourteen TP53 haplotypes were observed in the admixed populations, whereas only 3 to 5 in Amerindians. To our knowledge this is the first report of GST polymorphisms and TP53 haplotype distribution in Venezuelans. The distribution of most of analyzed polymorphisms in the urban sample is consistent with the admixed origin of the present-day population of Venezuela. While, the inter-ethnic variations in genetic polymorphisms found in Native American tribes seem to be the result of the influence of demographic factors. These results provide additional data for undertaking ethnographic and disease association studies in Venezuela.
authors.affiliation: Laboratorio de Genetica Molecular, Decanato de Ciencias de la Salud, Universidad Centroccidental Lisandro Alvarado, Barquisimeto, Venezuela. Electronic address: mchiurillo@ucla.edu.ve.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Chiurillo
authors.forename: Pedro
authors.initials: P
authors.lastname: Griman
authors.forename: Laskhmi
authors.initials: L
authors.lastname: Santiago
authors.forename: Keila
authors.initials: K
authors.lastname: Torres
authors.forename: Yeinmy
authors.initials: Y
authors.lastname: Moran
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Borjas
mesh_terms: D000483:Alleles; D005787:Gene Frequency; D014644:Genetic Variation; D005838:Genotype; D051549:Glutathione S-Transferase pi / Q000235:genetics*; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D009154:Mutation; D009369:Neoplasms / Q000235:genetics; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D014687:Venezuela / Q000208:ethnology
chemical_list: D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; D016159:Tumor Suppressor Protein p53; C413545:glutathione S-transferase T1
keywords: Amerindians; DNA; GSTM1; GSTP1; GSTT1; GSTs; HWE; Hardy–Weinberg equilibrium; LD; PCR; RFLP; SNP; TP53; Venezuelan population; deoxyribonucleic acid; glutathione S-transferase M1; glutathione S-transferase P1; glutathione S-transferase T1; glutathione S-transferases; linkage disequilibrium; polymerase chain reaction; restriction fragment length polymorphism; single-nucleotide polymorphism