Genetic Adaptations to New Environments in Human Populations

The history of human evolution and dispersal was associated with remarkable environmental changes over time and space, which resulted in major challenges to homeostatic systems. Professor Di Rienzo's group has developed approaches for detecting the impact of selective pressures associated with environmental factors and they have applied them to genome-wide genetic variation data sets collected in worldwide populations.  Using these approaches, they identify adaptations to selective pressures related to climate as well as diet and subsistence. Some of these beneficial alleles were selected in multiple continents while others are likely to represent new adaptations associated with specific dispersal events, e.g. the peopling of the Americas.  Interestingly, adaptations to new environments result from subtle frequency shifts at many loci, much like the susceptibility to common diseases is due to many risk alleles with small phenotypic effects, which suggests a similar genetic architecture. To apply a time scale to human adaptations, they use next generation sequence data and approximate Bayesian computation methods to estimate the age of beneficial alleles that influence immune response phenotypes.

Speaker: Anna DiRienzo

Room T175