Genetic basis of cold tolerance in Drosophila

We use the recurrent evolution of cold tolerance in Drosophila melanogaster during the worldwide expansion of the species as a study system for the genetics of adaptation. Elevated cold tolerance has evolved at least twice: one at a high-latitude region and the other at an African high-altitude region. For each of the two instances, we studied the genetic architecture of cold tolerance in a bulk segregant mapping framework by crossing strains from high- and low-cold tolerance populations. We then apply population genetic scans for local adaptation within our quantitative trait locus (QTL) regions. Finally, we performed the same analysis for an ethanol-resistant trait using the same sets of crosses and compared the QTLs between the two ecologically correlated traits.