MITOCHONDRIAL LINEAGES IN LADIN-SPEAKING COMMUNITIES OF THE EASTERN ALPS

European mitochondrial alleles cluster into five haplogroups. Haplogro up 2 is rare in general, but represents more than half of the few know n sequences among Ladin speakers of the Alps. Here we describe DNA div ersity in control region I of the hypervariable D-loop in 43 Ladins, a nd in 25 Italian speakers. Analysis of these data, and of previously p ublished sequences, confirms a high degree of differentiation among La dins and their geographical neighbours. This cannot be regarded as a s imple effect of isolating factors, geographic or linguistic, as divers ity is high within Ladin communities too. Rather, allele genealogies, population trees, and principal component analysis suggest a relations hip between Ladin and Near Eastern samples. Two evolutionary hypothese s seem compatible with these findings. The view whereby Ladins could b e descended from Palaeolithic inhabitants of the Alps is supported by the identification, in this study, of the probable ancestral haplotype of group 2, never previously observed in central Europe. Alternativel y, a comparatively recent, Neolithic immigration of the ancestors of c urrent Ladin speakers seems consistent with recent linguistic theories . In both cases, the number of lineages present, and their extensive d iversity, are not compatible with a serious bottleneck in the Ladin po pulation's history.