Early holocenic and historic mtDNA african signatures in the iberian peninsula: The andalusian region as a paradigm

Determining the timing, identity and direction of migrations in the Mediterranean Basin, the role of "migratory routes" in and among regions of Africa, Europe and Asia, and the effects of sex-specific behaviors of population movements have important implications for our understanding of the present human genetic diversity. A crucial component of the Mediterranean world is its westernmost region. Clear features of transcontinental ancient contacts between North African and Iberian populations surrounding the maritime region of Gibraltar Strait have been identified from archeological data. The attempt to discern origin and dates of migration between close geographically related regions has been a challenge in the field of uniparental-based population genetics. Mitochondrial DNA (mtDNA) studies have been focused on surveying the H1, H3 and V lineages when trying to ascertain north-south migrations, and U6 and L in the opposite direction, assuming that those lineages are good proxies for the ancestry of each side of the Mediterranean. To this end, in the present work we have screened entire mtDNA sequences belonging to U6, M1 and L haplogroups in Andalusians--from Huelva and Granada provinces--and Moroccan Berbers. We present here pioneer data and interpretations on the role of NW Africa and the Iberian Peninsula regarding the time of origin, number of founders and expansion directions of these specific markers. The estimated entrance of the North African U6 lineages into Iberia at 10 ky correlates well with other L African clades, indicating that U6 and some L lineages moved together from Africa to Iberia in the Early Holocene. Still, founder analysis highlights that the high sharing of lineages between North Africa and Iberia results from a complex process continued through time, impairing simplistic interpretations. In particular, our work supports the existence of an ancient, frequently denied, bridge connecting the Maghreb and Andalusia.Financial support was provided by the Spanish Ministry of Competitiveness through Research Project CGL2010-15191/BOS granted to RC and International Mobility Program Acciones Integradas Hispano-Portuguesas (PRI-AIBPT-2011-1004) granted to RC (Spain) and LP (Portugal) (http://www.mineco.gob.es/portal/site/mineco/idi). The E.C. Sixth Framework Programme under Contract n° ERAS-CT-2003-980409 (EUROCORES project of the European Science Foundation) also provided financial support to JMD for North African population research. CLH has a predoctoral fellowship granted by Complutense University. PS is supported by FCT Investigator Programme (IF/01641/2013). IPATIMUP (https://www.ipatimup.pt/) integrates the Instituto the Investigação em Saúde (i3S) Research Unit, which is partially supported by FCT, the Portuguese Foundation for Science and Technology. IPATIMUP is funded by FEDER funds through the Operational Programme for Competitiveness Factors - COMPETE and National Funds through the FCT - under the project PEst-C/SAU/LA0003/2013. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Mosaic maternal ancestry in the Great Lakes region of East Africa

The Great Lakes lie within a region of East Africa with very high human genetic diversity, home of many ethno-linguistic groups usually assumed to be the product of a small number of major dispersals. However, our knowledge of these dispersals relies primarily on the inferences of historical, linguistics and oral traditions, with attempts to match up the archaeological evidence where possible. This is an obvious area to which archaeogenetics can contribute, yet Uganda, at the heart of these developments, has not been studied for mitochondrial DNA (mtDNA) variation. Here, we compare mtDNA lineages at this putative genetic crossroads across 409 representatives of the major language groups: Bantu speakers and Eastern and Western Nilotic speakers. We show that Uganda harbours one of the highest mtDNA diversities within and between linguistic groups, with the various groups significantly differentiated from each other. Despite an inferred linguistic origin in South Sudan, the data from the two Nilotic-speaking groups point to a much more complex history, involving not only possible dispersals from Sudan and the Horn but also large-scale assimilation of autochthonous lineages within East Africa and even Uganda itself. The Eastern Nilotic group also carries signals characteristic of West-Central Africa, primarily due to Bantu influence, whereas a much stronger signal in the Western Nilotic group suggests direct West-Central African ancestry. Bantu speakers share lineages with both Nilotic groups, and also harbour East African lineages not found in Western Nilotic speakers, likely due to assimilating indigenous populations since arriving in the region ~3000 years ago

Discordant Patterns of mtDNA and Ethno-Linguistic Variation in 14 Iranian Ethnic Groups

Background/Aims: Present-day Iran has long represented a natural hub for the expansion of human genes and cultures. That being so, the overlapping of prehistoric and more recent demographic events interacting at different time scales with geographical and cultural barriers has yielded a tangled patchwork of anthropological types within this narrow area. This study aims to comprehensively evaluate this ethnic mosaic by depicting a fine-grained picture of the Iranian mitochondrial landscape. Methods: mtDNA variability at both HVS-I and coding regions was surveyed in 718 unrelated individuals belonging to 14 Iranian ethnic groups characterized by different languages, religions and patterns of subsistence. Results: A discordant pattern of high ethno-linguistic and low mtDNA heterogeneity was observed for the whole examined Iranian sample. Geographical factors and cultural/linguistic differences actually represented barriers to matrilineal gene flow only for the Baloch, Lur from Yasouj, Zoroastrian and Jewish groups, for which unusual reduced levels of mtDNA variability and high inter-population distances were found. Conclusion: Deep rooting genealogies and endogamy in a few of the examined ethnic groups might have preserved ancestral lineages that can be representative of Proto-Indo-Iranian or prehistoric mitochondrial profiles which survived relatively recent external contributions to the Iranian gene pool

The population history of the Croatian linguistic minority of Molise (southern Italy): a maternal view

This study examines the mitochondrial DNA (mtDNA) diversity of the Croatian-speaking minority of Molise and evaluates its potential genetic relatedness to the neighbouring Italian groups and the Croatian parental population. Intermatch, genetic distance, and admixture analyses highlighted the genetic similarity between the Croatians of Molise and the neighbouring Italian populations and demonstrated that the Croatian-Italian ethnic minority presents features lying between Croatians and Italians. This finding was confirmed by a phylogeographic approach which revealed both the prevalence of Croatian and the penetrance of Italian maternal lineages in the Croatian community of Molise. These results suggest that there was no reproductive isolation between the two geographically proximate, yet culturally distinct populations living in Italy. The gene flow between the Croatian-Italians and the surrounding Italian populations indicate, therefore, that ethnic consciousness has not created reproductive barriers and that the Croatian-speaking minority of Molise does not represent a reproductively isolated entity