Y-chromosome differentiation in Northwest Africa

Variation of seven Y-chromosomal DNA polymorphisms, one microsatellite (DYS 19), and six biallelic markers (DYS287, DYS271, SRY2627, SRY-1532, 92R7, an d M9), were studied in males from Northwest Africa. To evaluate the degree of differentiation in this region, males from neighboring areas such as the Iberian Peninsula and sub-Saharan Africa were also typed. The results show a large number of paternal lineages of Northwest African origin (over 75%) , supporting a long-term population continuity in the area. When the analys is of molecular variance (AMOVA) was performed both on the microsatellite a nd biallelic marker combinations or haplogroups, a large degree of differen tiation among areas was revealed. In spite of these geographic differences, some gene flow between areas was detected by the presence of haplogroups w ith other geographical origins.