CU researcher: 'Thrifty gene,' cause of obesity

Posted at 9:58 AM, Oct 01, 2015

A genetic mutation beneficial to ancient apes might be causing detrimental health issues for modern humans, a University of Colorado Anschutz Medical Campus researcher said in a recent article. 

Published in the October 2015 edition of Scientific American, the piece by professor of medicine Richard J. Johnson says a genetic mutation that occurred among prehistoric apes to survive food scarcity could be behind today’s pandemic of diabetes and obesity.

“These ancient apes were living primarily on fruit, which is rich in the sugar, fructose. At that time of global cooling, fruit became progressively less available in Europe where many of these apes were living,” said Dr. Johnson, whose expertise includes studying the underlying causes of obesity, kidney disease, diabetes and hypertension. “The resulting mutation caused an increase in uric acid levels.”

High uric acid levels are responsible for a number of diseases including gout, Johnson said, but he also found that it helps fructose store fat and induce insulin resistance.

“While this mutation would have been beneficial when food, especially fruit, was less available, in today’s society where many foods contain fructose from table sugar or high fructose corn syrup, it may well play be increasing our risk for developing obesity or diabetes,” Johnson said. 

But critics point out that periods of starvation among primates were rare and when they did occur they were too short for a mutation to develop.

After careful research, Johnson and several other colleagues from Anschutz and the Georgia Institute of Technology found evidence that a mutation in the uricase gene enhances the ability to convert fructose -- often obtained by eating figs -- to fat during famine. 

“Our hypothesis suggests that a mutation in a gene 15 million years ago, which was beneficial at that time, might now have a haunting role in the epidemics of obesity, diabetes, kidney disease and heart disease that are prevalent in our society today,” Johnson said.

Get breaking news on your phone, download the free 7NEWS app for iPhone/iPads, Android and Kindle. And follow us on Facebook, Twitterand Instagram.