Can epigenetics modulate the risk of type 2 diabetes?

The obesity epidemic has caused the number of cases of type 2 diabetes to skyrocket. Indeed, the nearly 650 million people worldwide who suffer from obesity are seven times more likely to develop the disorder. If waist size is the number one cause of type 2 diabetes, why aren’t all obese people affected by the disorder?

The risk of developing type 2 diabetes due to obesity is attributable to a combination of elements.

Different studies have shown that genetics come into play, albeit only to a certain degree, thus leading researchers to believe that there are other factors. Elin Grundberg, professor in the Department of Human Genetics at McGill University and lead investigator of the EpiTriO project that brings together collaborators in Canada, France and Germany, believes that the answer lies in the epigenome: a set of chemical changes—or epigenetic marks—that accumulate over time based on lifestyle and environment and alter certain gene functions.

Professor Grundberg and her team set out to test the hypothesis using fat samples from Québec’s human tissue bank at Université Laval collected during bariatric surgeries to compare different types of cells from diabetic and non-diabetic obese people. High-resolution images of the cells revealed differences in their composition and expression of various genes.

Elin Grundberg suspects that the risk of developing type 2 diabetes due to obesity is attributable to a combination of excess fat, genetic make-up and environmental epigenetic changes. The next step is to validate the observations with a larger group of obese patients. Her aim is to explain the origin of epigenetic marks. Do they stem from diet? Environmental factors? Heredity?

The researchers have ultimately set their sights on finding a way, ideally through a blood test, to quickly identify the markers of an increased risk of developing type 2 diabetes in people who are overweight. The screening would help prevent the disorder. For example, a patient could make dietary changes before the type 2 diabetes causes major physical and economic strain.