Analysis of Y chromosome lineages in a sample from Sub-Saharan Africa descendents in Rio de Janeiro

Abstract

Genetic differentiation can exist not only between populations but also between different groups within a population, which must have to be taken into account in forensic databasing. The analysis of Y chromosome SNPs has shown to be a powerful tool to detect population substructure, critical in admixed populations as it is the case of Brazilian as well as most American populations. With this work, we aimed to study the origin of paternal lineages (Y-SNPs) in a sample of Sub-Saharan Africa descendents living in Rio de Janeiro. A low proportion of YAP+ chromosomes were found (≈42%), a mutation usually represented in almost 80% of the male lineages in Bantu populations. Concerning the YAP− chromosomes, all of them carried the M89 mutation, and the most common lineages were those belonging to the European R1b1-P25 haplogroup, with a frequency of 37.12%. As expected, a much higher proportion of YAP+ chromosomes were found in this sample than in Rio de Janeiro general population (19%). Nevertheless, in accordance with other studies on African ancestry groups in America, our results revealed a high proportion of European Y lineages in Afro-Brazilians from Rio de Janeiro.