October 25, 2013
Scientists Find Rare Gene Mutation For Slow Metabolism And Overeating
[ Watch the Video: KSR2 Mutations are Associated With Obesity ]
Michael Harper for redOrbit.com - Your Universe Online
Researchers from the University of Cambridge say they’ve discovered a possible genetic origin for obesity which could slow the metabolism and drive a person to eat fatty foods. Though they say this genetic condition affects less than one in one hundred people, they were able to observe similar conditions in mice with the same genetic switches flipped.
Those who are affected by faulty genetics, however, are likely to be severely obese by the time they reach early childhood. Dr. I. Sadaf Farooqi of Cambridge University and team say the main suspect in their research is the gene KSR2 (Kinase Suppressor of Ras 2). When this gene is flipped off, it may trigger longer bouts of eating and slower metabolism, thereby leading to obesity. For study, Farooqi and team sequenced the DNA from over 2,000 severely obese patients, finding several variations of a KSR2 mutation. Their results are now published in the journal Cell.
"You would be hungry and wanting to eat a lot, you would not want to move because of a slower metabolism and would probably also develop type 2 diabetes at a young age," explained Farooqi in an interview with the BBC. "It slows the ability to burn calories and that's important as it's a new explanation for obesity."
Farooqi is quick to admit, however, that their studies show this mutation is rare and likely only affects young children who already show signs of obesity. All told, the research suggests that less than one percent of the population is affected by the gene, but two percent of young children who are already obese likely have a KSR2 mutation.
Doctors and researchers are often quick to dismiss the idea that being born with a slow metabolism could be to blame for severe cases of obesity. Those who do have a slower metabolism are usually found to have an underactive thyroid gland. Yet when Farooqi and team began sequencing the DNA from 2,101 severely obese patients, they found their thyroid glands were behaving normally. It’s also been suggested that some people simply burn calories more slowly than others, a hypothesis which may be supported by Farooqi’s research.
“Up until now, the genes we have identified that control body weight have largely affected appetite. However, KSR2 is different in that it also plays a role in regulating how energy is used in the body. In the future, modulation of KSR2 may represent a useful therapeutic strategy for obesity and type 2 diabetes.”
With this new study, Farooqi says there may be good cause to look into creating a drug to flip the KSR2 switch back into normal operating mode to prevent a lifetime of obesity and health problems in children.
This isn’t the first time medical science has sought a drug to rid the developed world of obesity, however. Previously researchers claimed they found a hormone responsible for giving some people to have larger appetites than others. The biochemical is technically known as ghrelin but is commonly referred to as the 'hunger hormone.' It had been assumed that if a drug could repress this hormone, it could help those who struggle with their weight to stop overeating.
Recent research has shown that while ghrelin may be responsible for triggering hunger, it’s also know to be triggered during long bouts of stress. This means drugs created to inhibit ghrelin may also one day be used to help those with post-traumatic stress disorder (PTSD).