Y -chromosome diversity in central Portugal reveals signatures of ancient maritime expansions
Martiniano, Rui; Feitosa, Yara; Abade, Augusto; Manco, Licínio
The genetic diversity of human populations in Portugal results from several different demographic events that occurred in distinct prehistorical and historical periods. The main objective of this study was to examine if patterns of Y-chromosome diversity explained by ancient maritime Mediterranean expansions can be observed in Coimbra district (central-west region of Portugal). A total of 125 male DNA samples were typed for 16 Y-SNPs and eight Y-STRs using standard molecular methodologies. Thirteen different haplogroups were identified, being the typical Western European haplogroup R1b1b2-M269 the most common (57.6%), followed by J-M304 (16%) and E1b1b1-M35 (12%). Haplogroup J-M304, whose origin maps to the Middle East, showed significant differences when comparisons were made between Coimbra district and the innermost region of Beira Interior (p = 0.022), in the same geographic area of the country, but not with the Portuguese regions of Alentejo (p = 0.165) and Algarve (p = 0.254), with known evidences of Mediterranean influence. Y-STR analysis revealed in Coimbra district several haplotypes previously associated with ancient maritime Mediterranean expansions. These findings suggest that maritime routes in the first millennium B.C. may have been important for introduction of new male lineages in Central Portugal.