Microsatellite studies on an isolated population of African descent in the Brazilian state of Bahia

Abstract

The African descent population of the Bananal community in the Brazilian state of Bahia (BA) was characterized as a genetic isolate and analyzed for some short tandem repeat (STR) microsatellite autosomic polymorphic loci (CSF1PO, TH01, TPOX, F13A1, FESFPS and vWA). These genetic variants were further compared to data obtained from an urban sample from the town of Jequié (BA) regarding demographic and anthropogenetic aspects. The Bananal sample comprised 32 unrelated individuals whereas Jequié was represented by 76 individuals. The Bananal Negroid Phenotypic Index (NPI) was 0.98 and the Negroid Cultural Index (NCI) 0.24. Consanguineous marriages occurred at a frequency of 34.61% and the F value was 0.0126. All six loci studied were in Hardy-Weinberg Equilibrium (p > 0.05). The genotypic and allele frequencies of the CSF1PO and vWA loci were similar. In the Bananal population the genic diversity of the THO1 locus was 66.8% and that of the F13A1 locus was 83.7%. The estimated ethnic racial admixture was 81% African and 19% Amerindian. The multiple correlation coefficient (R 2 ) indicated adequate adaptation (99%). Total genetic variation for the six loci was 82.9% with an index of 6.7% for population subdivision (G ST ' = 0.067). Anthropologic data and results obtained from the allele frequencies of the loci studied are indicative of a genetic isolate in Bananal, reminiscent of the a`quilombo community' (i.e. one founded by run away slaves).

HLA-Bw4-B*57 and Cw*18 alleles are associated with plasma viral load modulation in HIV-1 infected individuals in Salvador, Brazil

“…Additionally, environmental factors involved in HIV infection, such as social-economic and cultural factors, are also particular to this specifi c Brazilian region (Bahia), which resembles African countries, not only due to its genetic composition but also to social structure, culture, and health problems. 28,37 Therefore, we could deduce that the profi le of the association found here will be able to serve as orientation foretells for politics of public health, with reference to infection/illness prevention, and that the HLA profi le of the studied patients can be used for therapeutic monitoring in order to improve the effectiveness of the AIDS treatment.…”

A review of psychiatric genetics research in the Brazilian population

“…In recent years, a number of studies were conducted, showing that many of these populations exhibit a high inbreeding coefficient and an important role of genetic drift. 95,96 In those conditions, the total gene pool and number of different genes involved in a trait is limited and complex traits are expected to be more homogeneous, increasing the chance of success of a genetic association study.…”

So Close, So Far Away: Analysis of Surnames in a Town of Twins (Cândido Godói, Brazil)

“…There are examples of surname analyses in previously published research findings on the general population of Brazil (Azevêdo et al, 1969(Azevêdo et al, , 1980(Azevêdo et al, , 1982Stueber-Odebrecht et al, 1985;Cabello & Krieger, 1991;Leal Barbosa et al, 2006) and on Rio Grande do Sul in particular (Dornelles et al, 1999), where the clustering of mesoregions and a similarity in the frequencies of German surnames was also observed. The low diversity of surnames indicated that the state's population was becoming more homogeneous and still reflected the effect of more recent European migrations.…”