Admixture mapping in Brazilian patients with heart failure

Abstract

Cardiovascular diseases are the leading causes of death in many countries, including Brazil, and heart failure (HF) one of the most frequent diseases. Epidemiological and genetic studies have shown associations between ethnic origin of individuals and the development of various cardiovascular diseases. In previous study with patients with HF, through the analysis of genetic ancestry using 48 ancestry informative markers (AIMs) and mitochondrial haplogroups, our group showed an association between African haplogroups and increased risk for developing HF, while the Amerindian haplogroups were associated with a lower risk. Furthermore, we evidenced that patients of African haplogroups developed the disease earlier than the others. The analysis of AIMs showed that the major contribution of African autosomal ancestry conferred increased risk, whereas the major contribution of European autosomal ancestry conferred decreased risk for the development of HF, and patients with higher contribution of Amerindian autosomal ancestry had better survival rates in the period evaluation. The influence of phenotypes has been used to evaluate the prognosis of patients with HF, but a large number of cases of patients with similar phenotypes evolve in different ways. There is therefore a growing need for research on genetic factors that may influence an individualized prognosis. Using the admixture mapping technique can be found locus (loci) that contribute to genetic differences in phenotypes or diseases found among different ancestral populations of admixed populations and identify ancestry that is related to increased risk for various complex diseases such as HF. Therefore, this project has the overall objective to determine the genomic structure, using 650,000 Single Nucleotide Polymorphisms (SNPs), and genetic ancestry on a new sample of 500 patients with HF in order to replicate and refine the data obtained by our group. Still, due to the spatial resolution will be possible for large-scale genotyping, we will perform an analysis of admixture mapping with the objective of trying to map locations in the genome with distributed unequally among the different ethnic groups studied and that might help the identification of new variants genetic factors associated with a worse prognosis of HF. (AU)