Updated mtDNA study of Guinea-Bissau immigrant population living in Lisbon

Abstract

Guinea-Bissau is a country on the west coast of African Continent.Before the arrival of Europeans and until the XVII century, the territory was part of the Gabu kingdom, Mali Empire.In the past decades the number of immigrants in Portugal has grown and Guinean immigrant community is one of the largest immigrant communities. Most of those immigrants are based in Lisbon metropolitan region.Over the last decades, mtDNA has become an important genetic marker in human and population evolution studies, as well as in forensic and clinical case studies. Maternal inheritance, high copy number, lack of recombination and high mutation rateare characteristics that makes this genetic marker useful instudies of human origin and evolution.The non-coding mtDNAregion presents high genetic variability and the haplotypes obtained through the study of this region fall into haplogroups with specific polymorphisms shared by all individuals with a common ancestor.We studied 80 blood samples from Guinean immigrants living in Lisbon. mtDNA control region was amplified and sequenced between positions 16024 and 576, using two sets of primers - L15971/H016 and L16555/H639 -.The study of the control region revealed high genetic diversity within Guinean immigrants, with a high frequency of unique haplotypes. Most of the obtained mitochondrial DNAsequences belong to African haplogroups.As the result of the integration of African immigrants in Lisbon population we will have, in a near feature, individuals borned in Portugal with Portuguese nationality exhibiting mtDNA haplotypes typical of regions of the African Continent.