Research lines

Our current main lines of research are:

1. The population history of the European populations: The Genographic Project

In order to shed light to the reconstruction of human migrations through the analysis of genetic markers, National Geographic and IBM, with the participation of the Waitt Family Foundation, have launched The Genographic Project. This international project aims to provide genetic data in order to reconstruct human movements through the analysis of uniparental genomes (mitochondrial DNA and Y chromosome).

Within Western/Central Europe, we are proceeding with the sample collection and the first analyses of the results. These analyses will allow us to provide a finer resolution of the migrations within Europe and neighbouring geographic areas. More than 5,000 samples have already been collected and we are proceeding with the analyses of the Y-chromosome and mitochondrial DNA. The main questions to answer in Europe are the ones that have been posed for several years and not totally answered by genetic markers. To what extent the current European gene pool has been influenced by both Palaeolithic and Neolithic migrations? What was the role of the Last Glacial Maximum refugees and the subsequent recolonization of the continent? Was the Neolithic migration homogeneous across Europe? Can we correlate differences in archaeological Neolithic sites (linear pottery culture in Central Europe and impressed ware pottery in the Mediterranean) with different migratory waves? What was the influence of more recent migrations in the European genetic landscape? In order to address these questions we will use massive sample sizes, high resolution markers in the uniparental genomes, as well as standardized methods of analysis.

2. Evolutionary history and adaptations in Central African populations

Temporal and demographic inference of Pygmies and Bantu-speaker farmers through maternal lineages

The larger human African phenotypic and genetic diversity has been explained by the African origin of our species and the larger African population sample size. Nevertheless, the exact amount of genetic diversity within Africa 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 African biological diversity. One of these geographical areas not analysed in detail is Central (equatorial) Africa. These populations are located around the postulated Bantu expansion origin, a linguistic and technological expansion that originated in the Nigeria and Cameroon border. This expansion is related to the Bantu language dispersion, the iron technology and agriculture towards the south of the continent. Nonetheless, it is not known if this cultural expansion was related to a demographic expansion of farmers who replace and/or displaced the hunter-gatherer populations, or whether it was a cultural expansion without relevant demographic impact.

The present research line aims to study the genetic diversity in several Central African human 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. The comparison of genetic markers of hunter-gatherers and farmer might allow us to test if there was a population replacement during the Bantu expansion or a genetic continuity with cultural replacement. Additionaly, the analysis of whole genome markers allow us to evaluate those genomic regions that are responsible for some phenotypes, such as height, in some hunter-gatherer populations. This analysis suggests that some genes involved in development regulation are the responsible of the Pygmy phenotype.

3. The population structure of North African populations

Population genetic structure in North Africa

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.

4. The Roma: the demographic history of European Gypsies

Maternal lineages in Roma communities

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.

5. The origin and diversity of Catalan surnames

The Y chromosome is inherited from fathers to sons in a similar fashion as surnames. The present system of Catalan surnames is thought to be generated during the Middle Ages. The goal of the present project is to analyse the genetic diversity of the Y chromosome and its correlation with surnames.

We have selected 50 Catalan surnames based on their frequencies, distributions and categories. We want to address several questions such as, why are there some surnames that are more frequent than others? what is the correlation between surnames and Y-chromosome diversity? how often surnames are not joinly inherited with surnames? what is the origin of some surnames?

You can find more information in the web: cognoms.upf.edu