The rennin-angiotensin-aldosterone system (RAAS) is a critical pathway in regulating blood pressure and salt/water homeostasis, possessing an intimate relationship with the development of systemic artery hypertension (SAH). Once hypertension is considered a risk factor for coronary artery disease (CAD), the RAAS is also related to this pathology. This investigation aimed to analyse if the frequencies of AGT M235T (rs699) and ACE I/D (rs4646994) polymorphisms are associated with CAD and SAH in African-Brazilians and Caucasian-Brazilians. In this study we analysed 714 subjects who underwent coronary angiography to detect obstructive lesions and CAD, as well as blood pressure measurement and SAH, grouped according to ethnicity: 266 African-Brazilians and 448 Caucasian-Brazilians. Among CAD and SAH cases and controls, the genotype and allele frequencies of ACE I/D polymorphism were similar in both ethnic groups. The AGT 235TT genotype and 235T allele frequencies were higher in SAH cases (32%, 54.7%) versus controls in Caucasian-Brazilians (19.8%, 46.4%; P = 0.038, P = 0.031, respectively). The AGT 235TT (OR = 1.8; P = 0.028) demonstrated to be an independent factor risk in a multivariate logistic regression increasing SAH risk in Caucasians but not in African-Brazilians. In summary, AGT M235T polymorphism was associated with SAH risk in Caucasian-Brazilians, and no association was detected with CAD. No association was also observed in ACE I/D polymorphism either in CAD or SAH in African-Brazilians and Caucasian-Brazilians.

The understanding of the complex genotype-phenotype architecture of human pigmentation has clear implications for the evolutionary history of humans, as well as for medical and forensic practices. Although dozens of genes have previously been associated with human skin color, knowledge about this trait remains incomplete. In particular, studies focusing on populations outside the European-North American axis are rare, and, until now, admixed populations have seldom been considered. The present study was designed to help fill this gap. Our objective was to evaluate possible associations of 18 single nucleotide polymorphisms (SNPs), located within nine genes, and one pseudogene with the Melanin Index (MI) in two admixed Brazilian populations (Gaucho, N = 352; Baiano, N = 148) with different histories of geographic and ethnic colonization. Of the total sample, four markers were found to be significantly associated with skin color, but only two (SLC24A5 rs1426654, and SLC45A2 rs16891982) were consistently associated with MI in both samples (Gaucho and Baiano). Therefore, only these 2 SNPs should be preliminarily considered to have forensic significance because they consistently showed the association independently of the admixture level of the populations studied. We do not discard that the other two markers (HERC2 rs1129038 and TYR rs1126809) might be also relevant to admixed samples, but additional studies are necessary to confirm the real importance of these markers for skin pigmentation. Finally, our study shows associations of some SNPs with MI in a modern Brazilian admixed sample, with possible applications in forensic genetics. Some classical genetic markers in Euro-North American populations are not associated with MI in our sample. Our results point out the relevance of considering population differences in selecting an appropriate set of SNPs as phenotype predictors in forensic practice.

Our data suggests a low prevalence of celiac disease in African-derived Brazilian populations.

BackgroundRenal failure is common among older patients with sickle cell disease; this is preceded by subclinical glomerular hyperfiltration. Data about renal function of adults with sickle cell disease have been reported, but data on children is scarce, especially when comparing heterozygotic and homozygotic patients. ObjectiveThe goal of this study was to investigate the glomerular filtration rate of heterozygotic and homozygotic children with sickle cell disease. MethodsThe glomerular filtration rate of 11 children with sickle cell disease [7 homozygotic (SS) and 4 heterozygotic (SC)] with a mean age of 11 years (standard deviation: ± 5 years) was evaluated using standard laboratory techniques. Results are presented as descriptive analysis. ResultsOur results suggest that glomerular hyperfiltration is present in children with sickle cell disease; this is more evident in homozygotic than heterozygotic children. ConclusionThere is evidence of a need to monitor the renal function of children with sickle cell disease when special attention should be paid to homozygotic patients.

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).