One Genetic Mutation, Two Contrary Results, Says Small Study

The results of a small British study of insulin sensitivity among a group of people who carry a very specific genetic mutation suggest that that mutation drives down the risk for developing diabetes while at the same time increasing the risk for becoming obese. The results have surprised researchers from Oxford University who conducted the study.

According to their findings, published in the New England Journal of Medicine, patients who carry a mutation in the phosphate and tensin homologue gene (PTEN) also had significantly decreased levels of insulin resistance compared to a control arm of healthy counterparts.

Furthermore those carrier patients had a much higher BMI (mean: 32) compared to the controls (mean: 26) yet it was determined that they have increased levels of adiponectin compared to the control arm. Increased levels of adiponectin is expected in people with insulin sensitivity but not in patients whose BMI means that they are considered to be obese.

As mentioned earlier, this was a very small study, involving just 15 patients with the genetic mutation and 15 healthy matched controls from the Oxford BioBank, so further research will be necessary to confirm these findings. Further research will also be necessary to flesh out the exact role of the PTEN mutated gene especially as it relates to insulin resistance.

One researcher, Ulf Smith, MD and professor at University of Gothenburg in Sweden, wrote in an accompanying editorial for NEJM that the results of this trial "underscore concerns that therapeutic approaches aimed at increasing PTEN activity will effect a decrease in insulin sensitivity and will increase the risk of type 2 diabetes."

Source: MedPage Today