Distribution of the CCR5delta32 allele (gene variant CCR5) in Rondônia, Western Amazonian region, Brazil.

Since around 1723, on the occasion of its initial colonization by Europeans, Rondonia has received successive waves of immigrants. This has been further swelled by individuals from northeastern Brazil, who began entering at the beginning of the twentieth century. The ethnic composition varies across the state according to the various sites of settlement of each wave of immigrants.

Distribution of hemoglobin phenotypes in four different districts of Porto Velho, Rondônia, Brazil.

Hemoglobin profile studies have been carried out in four samples from different districts of Porto Velho (Rondônia State) in the western Amazonian region of Brazil: Candelária, Bate Estaca, Hemeron (at the State Blood Bank), and São Carlos. Samples from 337 unrelated individuals were collected during medical and paramedical team visits by professionals from the Instituto de Pesquisa em Patologia Tropical and the Centro de Pesquisa em Patologias Tropicais (both research institutes in tropical diseases). The aim of this study is to assess the frequency of alleles in the hemoglobin system, mainly alleles HB*A, *S, and *E.

CFTR haplotype distribution in the Brazilian Western Amazonian region.

Two hundred twenty-one individuals from four groups located around the Brazilian town of Porto Velho, Rondônia, were studied in relation to four sites located within or near the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The allele frequencies, when considered individually, do not depart markedly from frequencies obtained from other populations of mainly European descent. However, when haplotypes were estimated, two of the groups departed markedly from other Brazilian and non-Brazilian samples.

Expression of class mu glutathione-S-transferase in human liver and its association with hepatopathies.

We studied the distribution of GSTM1 phenotypes in 611 individuals from an ethnically mixed sample of the Brazilian population who died from various causes. No influence of age, gender, or ethnicity was detected on the phenotypic distribution. In a sub-sample of 66 alcoholic individuals compared with 399 non-alcoholics there was almost a doubling of the odds ratio for GSTM1(0) individuals in the alcoholic category.

The association of genetic markers and malaria infection in the Brazilian Western Amazonian region.

Almost all individuals (182) belonging to an Amazonian riverine population (Portuchuelo, RO, Brazil) were investigated for ascertaining data on epidemiological aspects of malaria. Thirteen genetic blood polymorphisms were investigated (ABO, MNSs, Rh, Kell, and Duffy systems, haptoglobins, hemoglobins, and the enzymes glucose-6-phosphate dehydrogenase, glyoxalase, phosphoglucomutase, carbonic anhydrase, red cell acid phosphatase, and esterase D). The results indicated that the Duffy system is associated with susceptibility to malaria, as observed in other endemic areas.