[PROVISIONAL] A systematic scoping review of the genetic ancestry of the Brazilian population

• Main Authors: Aracele Maria de Souza, Sarah Stela Resende, Taís Nóbrega de Sousa, Cristiana Ferreira Alves de Brito
• Format: Article
• Language: English
• Published: Sociedade Brasileira de Genética
• Series: Genetics and Molecular Biology
• Subjects: scoping review; genetic ancestry; Brazilian population; genetic admixture
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572019005020104&lng=en&tlng=en

Abstract The genetic background of Brazilian population is mainly characterized by three parental populations: European, African and Native American. The aim of this study is to overview the genetic ancestry estimates for different Brazilian geographic regions and analyzed factors involved in these estimates. In a systematic scoping review were included fifty-one studies, comprehending 81 populations of 19 states from five regions of Brazil. To reduce the potential bias of studies with different sampling, we calculated the mean of genetic ancestry weighted by the number of individuals. The weighted mean proportions of European, African and Native American ancestries were 68.1%, 19.6% and 11.6%, respectively. At the regional level, the highest European contribution occurred in the South, while the highest African and Native American contributions occurred in the Northeastern and Northern regions, respectively. Among states in the Northeast region, Bahia and Ceará showed significant differences among them, suggesting distinct demographic histories. This review contributes for a broader understanding of the Brazilian ancestry estimates and also identify that the ancestry estimates were influenced by the type of molecular marker and the sampling.