Our early human ancestors originated from a hot, humid climate where natural selection focused on dispersing heat.  As humans migrated to colder climates there would have been evolutionary pressure to adapt to their new settings by boosting the processes that produce and retain heat.
Genes involved in energy metabolism are therefore likely to be central to heat and cold tolerance. 
Researchers from the Dept of Human Genetics, University of Chicago, USA tested this theory by genotyping 873 tag SNPs in these ‘cold tolerance’ genes in 54 worldwide populations and found a correlation with climatic variations.
Among the results were strongest signals from several SNPs, that had previously …read more