Researchers from the University of Chicago have discovered that many of the genetic variations that have enabled human populations to tolerate colder climates may also affect their susceptibility to metabolic syndrome, a cluster of related abnormalities that include obesity, elevated cholesterol levels, heart disease, and diabetes.
Scientists have long noted that humans inhabiting colder regions were bulkier and had relatively shorter arms and legs. In the 1950s, researchers found correlations between colder climates and increased body mass index (BMI), a measure of body fat, based on height and weight. Now scientists have found a strong correlation between climate and several of the genetic variations that appear to influence the risk of metabolic syndrome, consistent with the idea that these variants played a crucial role in adaptations to the cold. Also, some genes associated with cold tolerance have a protective effect against the disease, while others increase disease risk.