Saami and Berbers--an unexpected mitochondrial DNA link

Abstract

The sequencing of entire human mitochondrial DNAs belonging to haplogroup U reveals that this clade arose shortly after the "out of Africa" exit and rapidly radiated into numerous regionally distinct subclades. Intriguingly, the Saami of Scandinavia and the Berbers of North Africa were found to share an extremely young branch, aged merely approximately 9,000 years. This unexpected finding not only confirms that the Franco-Cantabrian refuge area of southwestern Europe was the source of late-glacial expansions of hunter-gatherers that repopulated northern Europe after the Last Glacial Maximum but also reveals a direct maternal link between those European hunter-gatherer populations and the Berbers.

Figure 1

Tree of 39 mtDNA sequences belonging to haplogroup U. The tree, rooted using the reference sequence (rCRS) (Andrews et al. 1999) as an outgroup, illustrates subhaplogroup affiliations. The sequencing procedure and phylogeny construction were performed as described elsewhere (Torroni et al. ; Achilli et al. 2004). For phylogeny construction, the highly variable site 16519 and the length variation in the poly-C stretch at nts 309–315 were not used, and half the weight was assigned to the control-region mutations, relative to that assigned to coding-region mutations. Mutations are shown on the branches; they are transitions, unless a base change is explicitly indicated. Insertions are suffixed with a plus sign (+) and the inserted nucleotide(s), and deletions have a “d” prefix. Recurrent mutations are underlined; pathological mutations are in italics. The ethnic/geographic origins of mtDNAs are as follows: Pakistan (1–3, 12, and 13), Spain (4, 8, 14, 23, 36, and 39), Yemen (5 and 7), Adygei (6, 10, 18, and 20), Italy (9, 15–17, 19, 21, 22, 24, 31–33, 35, and 37), Ethiopia (11 and 38), Berber (30 and 34), Saami (25, 26, and 28), Yakut (27), and Fulbe from Senegal (29).