Laurent Excoffier
Computational and Molecular
Population Genetics Group
University of Bern
Group Webpage

What do we do?

In the Computational and Molecular Population Genetics (CMPG) Group, we develop new methodologies for the simulation and analysis of molecular polymorphisms within species, with a particular focus on humans. We also develop and maintain the Arlequin software, a popular package for the analysis of multi-locus genetic diversity within and between populations, as well as statistical methods to reconstruct and infer evolutionary processes from genomic data. The team focuses on the effect of range expansions on genomic and functional diversity, and the detection of signatures of adaptation and selection at the molecular level.

Highlights 2017

In 2017, our group was involved in the analysis of the effect of range expansions on the fitness of bacteria. We showed that bacteria accumulated deleterious mutations during their expansions on Petri dishes, confirming some of our theoretical predictions. We have continued investigating past human history, this time by investigating the relatedness of a 34 ky old Siberian individual from the Sunghir site, showing he was more related to present Europeans than to present Asians. We have also been involved in the development of new methodologies to detect polygenic selection. We first proposed a likelihood ratio test to detect gene sets under selection in the primate ancestors of humans. We then developed a new method to detect subsets of connected genes that belong to one or several biological pathways. We have applied the latter methodology to the detection of sets of genes involved in adaptation to altitude in humans.

Main publications 2017

  • Sikora M et al. Ancient genomes show social and reproductive behavior of early Upper Paleolithic foragers. Science 2017 358: 659-662
  • Bosshard L et al. Accumulation of deleterious mutations during bacterial range expansions. Genetics 2017 207: 669-684
  • Gouy A et al. Detecting gene subnetworks under selection in biological pathways. Nucleic Acids Research 2017 45(16): e149

Our main research topic: