Recent genetic discoveries have taught researchers a lot about type 2 diabetes, and identified particular genetic variants that can influence a person’s risk of developing the condition.

But two studies published this week in the New England Journal of Medicine conclude that genetic information still pales in comparison to factors like body weight, smoking, cholesterol levels and other medical diagnostics when it comes to predicting who will develop the condition.

The papers are a reminder that although personal genomics promises to become a valuable supplement to preventive medicine, the information it provides shouldn’t be considered a replacement for regular check-ups and a healthy lifestyle. And though genetics certainly plays a role, diet, exercise and other environmental factors have a substantially greater impact on whether a person will develop type 2 diabetes.

Both studies looked at one-letter DNA variations known as single-nucleotide polymorphisms (SNPs) that have been linked to diabetes. The 23andMe Personal Genome Service™ provides information on nine diabetes-associated SNPs.

One study used data from the legendary Framingham Heart Study, which has followed three generations of participants over a period of 60 years, to show that inheriting a greater number of high-risk diabetes genes does increase a person’s chances of developing the condition. But when added to traditional measures of diabetes risk such as family history, body-mass index, fasting plasma glucose level and blood pressure, a person’s genotype at the 18 SNPs studied did not significantly improve the researchers’ ability to predict which of the 2,377 study participants became diabetic over a period of 28 years.

The other study, which looked at 16 SNPs in 16,061 Swedish and 2,770 Finnish subjects who had been followed for an average of 23.5 years, produced a similar result. The authors concluded that “common genetic variants associated with the risk of diabetes had a small effect on the ability to predict the future development of type 2 diabetes.”

However, because the physiological risk factors typically develop later in life (though they are becoming distressingly common in younger populations) the authors of the Framingham-based study suggest genetic information could be useful in motivating young people who have inherited a high diabetes risk to control their weight and take other preventive measures.

And research is bound to produce more knowledge about the genetic roots of diabetes. So in the not-too-distant future, a person’s genotype is likely to provide substantial predictive information beyond what is available from family history and physiology.

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23andMe presented yesterday at the 11th Milken Institute Global Conference, taking place through Wednesday in Los Angeles. The conference has a significant health care focus, with session topics ranging from “Is the Pharmaceutical Well Drying out?” to “What kind of Reform Makes Sense?”

There were also a number of developing world topics, and 23andMe had the pleasure of sitting on a panel entitled “Revolutionizing Health Care and Research in the Developing World,” which included Muhammad Yunus, founder of the Grameen Bank and recipient of the 2006 Nobel Peace Prize for his pioneering work in microfinance.

While 23andMe is not currently involved in research projects in the developing world, we recognize that it’s important to start thinking about how we could get involved soon. This goes in line with two important goals of the company: actively engaging researchers and individuals from around the world to create truly global research projects and filling in the gaps in research where populations are currently underrepresented.

Type 2 diabetes is a good example. While type 2 diabetes is a significant issue in the US and Europe, it is also a major health problem in South Asia. 23andMe currently looks at nine SNPs that have been associated with type 2 diabetes. Unfortunately, the majority of those SNPs have only been studied in European populations – leaving us to wonder what they mean for other groups. 23andMe hopes to undertake global research projects in type 2 diabetes to better understand the genetics in all different populations.

The Milken Institute panel discussion concluded with a proposal from 23andMe to Muhammad Yunus that we collaborate on his new Grameen Health Care Initiatives to develop a project in Bangladesh or India. We strongly believe that by involving populations from around the world we will have a much better understanding of genetics and environment – and that will hopefully bring better health care for all of us.

Photo by Hossain Toufique Iftekher

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