1.- The population structure of North African populations

Human populations in North Africa are completely different from the rest of the continent in genetic terms, since its settlement and its posterior contacts have been almost independent from the sub-Saharan area. The human movements in this region have been constrained by the Mediterranean Sea and the Sahara Desert, which have limited the migrations into an east-west direction, although these barriers have not been totally impermeable to human movements.

The present research line aims to analyze the genetic diversity of human North African populations in order to establish their population structure and determine the impact of several cultural and historical migrations into the gene pool of the extant North African groups. Several human populations are been analyzed using high resolution uniparental markers (mitochondrial DNA and Y-chromosome) in order to define maternally- and paternally-inherited lineages, and whole genome autosomal markers (SNPs) and copy number variants (CNV) .

The goal is correlate genetic, geographic and linguistic diversity of these populations, compare them to other surrounding populations and test demographic hypotheses. If the Mediterranean and the Sahara have acted as strong genetic barriers, differences in population structure and composition of uniparental lineages will be observed when comparing North African results with surrounding populations. Possible gene flow can be determined, quantified, and dated. In addition, if cultural migrations (such as the Neolithic or the Arabization of the region) have acted differentially along the North African territory, genetic differences (in uniparental lineages and autosomal markers) between groups will be detected, quantified and dated. Finally, the refined phylogeography of uniparental genomes jointly with the analysis of whole genome data are been used to detect sexual migration asymmetries in North African populations.


2.- The Roma: the demographic history of European Gypsies

Although the exact figures are uncertain, the population size of Roma in Europe according to the Council of Europe might range from 10 to 12 million, with the largest numbers concentrated in Central and South-Eastern Europe where they might comprise more than 7% of the population in some countries. Mainly of nomadic lifestyle and with endogamous social practices, the geographically dispersed Roma groups have been socially marginalized and historically persecuted. The dispersion of Roma through Europe might represent one of the most remarkable human movements in the continent in historical times. Unfortunately, no written records are available for this diasporic process. Linguistic, anthropological, and genetic evidences point to an Indian origin of the Roma, which might have left the Indian sub-continent approximately between the 5th and 10th centuries.

Our goal is to unravel, through the analysis of uniparental and whole genome autosomal markers, the geographic origin of the Roma, their migration routes to Europe, their settlement in Europe, the admixture with host populations and the sexual asymetry of the admixture.


3.- Evolutionary history and adaptations in American populations

The Americas was the last continent to be occupied by humans and it has act as a sink of human migrations since then. Since the initial colonization, Native Americans were diverging in the continent yielding a myriad of peoples and cultures. In historical times, the arrival of the Europeans and slaved Africans had a dramatic impact in the culture and demography of Native groups, with reduction of the populations and extensive admixture events. Nevertheless, the exact amount of genetic diversity within America is unknown because there is a large number of populations, not analysed in detail, that have been involved in relevant cultural and demographic processes in the making of the American biological diversity. 

The present research line aims to study the genetic diversity in several American human populations, Native Americans and admix populations, using the analysis of uniparental genetic markers and autosomal markers in order to correlate linguistic, geographic and genetic diversity of these populations, test demographic hypotheses, and unravel those genomic regions associated with some specific phenotypes


4.- Functional implications of recent demographic events

Demographic events such as bottlenecks, isolation, founder effects, left traces in human populations. The reduction of sample size might have implications in the functional variants of our genomew since natural selection is less efficient in those groups that have experienced a dramatic population decline. Following this rationale, we aim to assess the impact of demography in human populations that have experienced a significant reduction of their population size. In this sense, we address this goal in the Roma, north African groups, and also in American populations.