The Genetic Connection In Type 2 Diabetes – “A Mess”
You’re probably familiar with the list of risk factors which increase the likelihood that a person will develop type 2 diabetes – age, excess body weight, sedentary lifestyle, ethnicity, having had gestational diabetes during a pregnancy, and family history of type 2 diabetes. The statistical association of type 2 diabetes with a family history of type 2 diabetes is strong (50% for a child if both parents have type 2 diabetes), and would certainly seem to point to inheritable genetic mutations which could be identified with techniques developed in the “human genome project.” But, the results of a large study (111,548 subjects) recently published in Nature using just those techniques showed how elusive these genetic anomalies can be. Michael White, Assistant Professor of Genetics at Washington University, titled his commentary on this study result in the Pacific Standard, The Genetics of Type 2 Diabetes Is a Mess.
In simplest terms, the study identified or verified (from previous studies) many “common” genetic mutations associated with an increased risk for type 2 diabetes, but these “common” genetic variations only account for about 10% of the risk associated with family history. The study, therefore, searched the genetic information of this huge group of subjects looking for other mutations – “rare” mutations – which could explain the missing risk factors (90% of the risk) associated with family history. For the most part, they didn’t find them. According to Professor White “after more than a decade of large, high-tech studies, the genetic basis of diabetes remains, for the most part, unexplained.”
What does this mean to you, and to your children and grandchildren, in a practical sense? First, it means that the new capacity of medical genomic science to use genetic information for “individualized” disease interventions is not close with type 2 diabetes – prevention and management is still where our practical focus should be. Second, for the good news, we know how to do effective prevention and management with diet, physical activity, and medication – we just have to do it. Remember, type 2 diabetes cases in the U.S. didn’t rise from 5 million to 30 million since 1980 as a result of genetics – it’s lifestyle that triggers genetic risk factors to become full blown type 2 diabetes, and it’s lifestyle that we have the freedom to change.
Have you experienced any complications associated with your diabetes?