Did you know DNA influences your fat processing and lipid levels?
The untold story of diabetes - Lipids and the risk of type 2 diabetes
Matthew always described himself as portly. Sure, his weight fluctuated a few times in his life, but to Matthew, his weight wasn’t a problem. He felt comfortable in his body, until he started falling asleep mid-conversation. No matter how many hours of sleep he clocked, he was always tired and sleepy. A doctor’s visit changed his whole life. He was diagnosed with type 2 diabetes.
Type 2 diabetes is a complex disease with several different risk factors. Obesity is the strongest risk factor, especially since a shared set of DNA changes underly both conditions. FADS1 is one such ‘diabesity’ gene that contributes to both our risk of obesity and type 2 diabetes.
We often associate diabetes with high sugar, but sugar is not the only culprit behind type 2 diabetes. Both obesity and type 2 diabetes are metabolic diseases, meaning they are triggered by our body’s inability to properly process dietary components, like sugars and fats. Fatty acid desaturase 1 (encoded by the FADS1 gene) participates in the metabolism of fatty acids. The FADS1 enzyme processes the ‘healthy’ fats, like omega-3 and omega-6, so they can be incorporated into our vital cellular membranes. These processed fatty acids also act as signalling molecules to stimulate the secretion of insulin and remove sugar from the blood.
Studies show that the amount of fatty acids in our blood, as well as their degree of saturation (the number of hydrogen atoms attached to a fatty acid), can drastically affect insulin secretion. This is how FADS1 activity is linked to the risk of type 2 diabetes. People with the rs174550 variant of FADS1 have lower levels of FADS1; hence are not quite as efficient at processing dietary fats. This leads to changes in the composition of cellular membranes, and is also linked to altered lipid levels and elevated blood glucose.
There are two possible explanations as to exactly how FADS1 rs174550 increases our risk of type 2 diabetes. Either it alters the level of signalling molecules that are important for insulin secretion or the changes in our cell membranes impair the release of insulin. While scientists are still trying to puzzle out the exact mechanism, what we do know is that inheriting rs174550 increases our risk of metabolic disorders like type 2 diabetes and obesity.
Diabetes was first described in a manuscript from Egypt dated 1500 BCE. Even thousands of years later, we still don’t have a cure for diabetes. On the brighter side, in their pursuit to cure diabetes, scientists have uncovered many of the factors that contribute to our predisposition to type 2 diabetes, offering us a fighting chance against this complex and debilitating disease.