A University of Alberta team of researchers has discovered an additional 2 million Canadians who have a high fat diet or are overweight may be at increased risk for developing type 2 diabetes if they carry a particular type of common specific genetic trait known as a polymorphism.
In work published today in the journal, Diabetes, pharmacology professor Peter Light and graduate student Michael Riedel suggest that saturated and trans fats are much more effective activators of a specific potassium channel found in the pancreas - known when activated to reduce insulin secretion from the pancreas and increase blood sugar levels. This effect, they say, is amplified in the polymorphic potassium channel. Interestingly, it seems that polyunsaturated fats are poor activators of the potassium channel.
"We're suggesting that people with this specific potassium channel polymorphism - about 2 million Canadians - may be more susceptible to type 2 diabetes if they have a high fat diet or are overweight, two of the biggest risk factors for type 2 diabetes," Dr. Light explains. "This may explain why 20 percent of type 2 diabetic Caucasians carry two copies of this polymorphism in their genes compared to only 10 percent in the non-diabetic Caucasian population."
The researchers say this discovery opens up the distinct possibility of specific genetic screening of people at risk for type 2 diabetes, which would then give physicians additional information to advise their high-risk patients on preventative diet and exercise options.
About 10 percent of non-diabetic Caucasians who possess this polymorphism may be at increased risk of developing type 2 diabetes if they consume a diet rich in saturated and trans fats. These findings provide a plausible "missing link" between common genetic variations and environmental risk factors for this very prevalent disease, Dr. Light explains.
The most recent findings build on their previous work. Back in 2003, the group published a brief genetics report in Diabetes showing that this common polymorphism in a potassium channel that controls insulin secretion is much more susceptible to being activated by intracellular fats.