Prevalence of CCR5-Δ32 and CCR2-V64I polymorphisms in a mixed population from northeastern Brazil.

Chemokines are low-molecular weight proteins that play a key role in inflammatory processes. Genomic variations in chemokine receptors are associated with the susceptibility to various diseases. Polymorphisms in chemokine receptor type 5 (CCR5)-Δ32 and CCR2-V64I are related to human immunodeficiency virus infection resistance, which has led to genetic association studies for several other diseases. Given the heterogeneous distribution of these polymorphisms in different global populations and within Brazilian populations, we analyzed the prevalence of CCR5-Δ32 and CCR2-V64I polymorphisms in a mixed population from northeastern Brazil. The study included 223 individuals from the general population of the city of Parnaíba, Piauí, who had a mean age of 73 years. Of these individuals, 37.2% were men and 62.8% were women. Polymorphisms were analyzed using DNA extracted from peripheral blood leukocytes by using polymerase chain reaction alone (CCR5-Δ32) or accompanied by restriction endonuclease digestion (CCR2-V64I). In both cases, the genotypes were determined using 8% polyacrylamide gel electrophoresis and silver nitrate staining. The population conformed to Hardy-Weinberg equilibrium for both the loci studied. No individuals were homozygous for allele-Δ32, which was present in 1.8% of the population, whereas allele-64I was present in 13.9% of the participants studied; 74.9% were homozygous for the wild-type allele, while 22.4 and 2.7% were heterozygous and homozygous for the mutant allele, respectively. Additional studies are needed to investigate the relationship between these polymorphisms and disease etiopathogenesis in reference populations.

Frequency of SNP -336A/G in the promoter region of CD209 in a population from northeastern Brazil.

Dendritic cells (DCs) mediate the initiation of the immune response against a variety of pathogens. The DC-SIGN receptor is encoded by the gene CD209 and is expressed on the surface of DCs. It binds to mannose-rich carbohydrates and enables the recognition of bacteria, fungi, parasites, and viruses. SNP -336A/G in the promoter region of CD209 influences the expression of the DC-SIGN receptor. Several studies have associated this SNP with an increased susceptibility to infectious diseases and the development of more severe forms of disease. Therefore, the aim of this study was to determine the prevalence of SNP -336A/G in a population from northeastern Brazil. We analyzed 181 individuals from the general population of Parnaíba, Piauí, Brazil, of which 37% were men and 63% were women. SNP -336A/G was detected by polymerase chain reaction and treatment with the restriction enzyme MscI and visualized by electrophoresis on an 8% polyacrylamide gel stained with silver nitrate. Of the individuals analyzed, 116 (64.1%) were homozygous AA, 57 (31.5%) were heterozygous (AG), and 8 (4.4%) were homozygous GG. The allele frequency of -336G was 20.2%. Genotype frequencies were in Hardy-Weinberg equilibrium. To the best of our knowledge, this is the first report to describe the frequency of the CD209 SNP -336A/G in a population in the State of Piauí. Further studies are needed to determine the relationship between this SNP and the vulnerability of this population to major infectious diseases.

Prevalence of variants that confer risk for venous thromboembolism in an elderly population of northeastern Brazil.

Venous thromboembolism (VTE) is an important cause of morbidity and mortality stemming from cardiovascular disease. It is a multifactorial disease caused by a combination of acquired risk factors, of which advanced age is the most significant, and genetic factors, including the variants FV G1691A, FII G20210A, and MTHFR C677T. We estimated the prevalence of these genomic variants in an elderly population of northeastern Brazil. The study included 188 elderly persons (65-93 years), of which 68 (36.2%) were men and 120 (63.8%) were women. Variants were detected by polymerase chain reaction-restriction fragment length polymorphism analysis, and subsequent electrophoresis on an 8% polyacrylamide gel stained with silver nitrate. The study population was in Hardy-Weinberg equilibrium for the 3 loci. Of the individuals analyzed, none carried variants of FV or FII (0%), and 24.7% had the MTHFR C677T polymorphism: 59 subjects (31.4%) were heterozygous (CT) and 17 subjects (9%) were homozygous (TT). Based on the analysis of these particular genes, we conclude that the study population does not present an increased risk for the development of VTE. Faced with a growing aging population worldwide, similar studies in other countries will help in the prevention of VTE in older individuals.