23andMe announced yesterday that it will begin offering a new type of report, called a genetic health predisposition report, for type 2 diabetes. The goal of the report is to give customers insight into their likelihood of developing type 2 diabetes, based on their DNA.
“Diabetes is a significant health issue in the United States that is expected to impact nearly half of the population. When customers learn about their genetic likelihood of developing type 2 diabetes, we believe there is an opportunity to motivate them to change their lifestyle and ultimately to help them prevent the disease,” said Anne Wojcicki, CEO and co-founder of 23andMe.
The intent of the genetic test is not to make a diagnosis. Rather, it offers a prediction of risk. The test is based on a polygenic risk score (PRS), used to stratify patients into risk categories based on their genetic mutations. It is unusual for a disease to be caused by mutations in a single gene. Much more commonly, diseases (such as type 2 diabetes, cardiovascular disease, and brain disorders) are mediated by a collection of common and low-frequency genetic variants, most of which remain unknown. Each variant has a small effect, but, taken together, they could indicate a person’s overall risk.
23andMe noted that this report could help by identifying and alerting people who may not know that they have a genetic predisposition for diabetes. This may prove useful in a disease like type 2 diabetes which can be delayed or even prevented through diet and lifestyle changes.
But, disease risk is frequently more complicated than genetics, which calls into question the usefulness of PRS. Disease risk can be broken down, generally, into three main factors: genetic susceptibility, environmental exposures, and lifestyle factors. And, for some diseases, the genetic component is not the most important factor. Indeed, for type 2 diabetes, some clinicians note that they can make the same prediction using a scale and blood sugar measurement.
With the American Diabetes Association estimating the costs of treating diabetes at more than $327 billion, any information that can alert people of the condition may be one worth trying. Along with looking at the genetic factors, the report also informs customers how other factors such as their weight, age, and lifestyle may influence the likelihood of developing the condition and what actions might make a difference. It also provides educational resources on type 2 diabetes.
23andMe has recently collaborated with Lark Health, a consumer platform using A.I. coaching to manage and prevent chronic disease, to give 23andMe Health + Ancestry Service customers the opportunity to access applications that incorporate their genetic results for diabetes prevention and weight loss counseling.
23andMe notes that this new type 2 diabetes report is different from other 23andMe health reports because “it was developed and entirely validated using 23andMe research data from more than 2.5 million 23andMe customers who have opted into research. Using this data, 23andMe scientists developed a polygenic score that drew on more than 1,000 genetic variants to calculate a customer’s likelihood of developing type 2 diabetes.” Given 23andMe’s access to enormous amounts of genetic information, it begs the question of what other diseases they will be able to predict risk for in the future.