An “amazing tour de force” study says a fat gene revolutionizes weight loss, reported the Associated Press on August 19. Scientists have finally traced how the FTO gene (the key obesity gene) makes people fat. Blocking the FTO gene with an obesity drug could bypass diet and exercise, as the only approaches to losing weight! Fellow scientists are lauding the study from MIT and Harvard researchers as solving a big mystery.
Researchers have known since 2007 that the fat gene FTO was related to obesity, but they didn’t know how. They couldn’t link it up to appetite or other known weight gain factors. The MIT-Harvard study showed that a faulty version of the fat gene causes energy from food to be sidetracked and stored as fat instead of burned. Genetic modifications on mice and in human cells shows this can be reversed.
One experiment blocked the faulty gene in mice and they became 50 percent despite eating a high-fat diet. They burned more energy even when asleep. In tests on human cells, blocking the fat gene increased energy burn in fat cells and restored normal metabolic function.
This study is revolutionary because it challenges long-held beliefs that people get fat by choosing to eat too much and exercise too little, explains study leader Melina Claussnitzer, a genetics specialist at Harvard-affiliated Beth Israel Deaconess Medical Center. Now genetics shows a third factor involved in obesity. Understanding the fat gene stores fat gives means drugs could be developed to redirect fat cells to operate differently. Obesity drugs currently on the market don’t target metabolism. They’re aimed at the brain and appetite.
But it’s not foolproof. Researchers say any pill developed from these findings won’t let users eat whatever they want without getting fat. They don’t know how altering fat storage gene might affect other things. The fat gene also didn’t explain all obesity. Only 5 percent of blacks have it, compared to 44 percent of whites. Researchers say other genes are at work, and diet and exercise still matter.
Also, it doesn’t explain away all fat. People with two faulty copies of the gene (from maternal and paternal side) only weighed about 7 pounds more than those without fat genes. Overweight and obese people are generally exponentially more than seven pounds overweight. But, cautioned one MIT professor Manolis Kellis, even seven on a healthy and an unhealthy weight.
The FTO gene influences obesity indirectly. It’s the controller for two other genes that govern thermogenesis (metabolism). Scientists have long known that “good fat” or brown adipose tissue burns calories. The more common white fat stores them. The body constantly makes fat cells: these two genes decide if they’ll be brown fat or white fat. Some companies are working on drugs to stimulate brown fat as opposed to white.
If the FTO gene influences other obesity factors like behavior and appetite, a blocker could treat all the components of obesity. Kellis and Claussnitzer are seeking a patent related to their work. Obesity affects over 500 million people worldwide and causes numerous related diseases. In the U.S., two-thirds of adults are overweight and half of those are obese.