Obesity

Researchers say the gene is present in all creatures, and could eventually be manipulated in humans to help them shed weight.

Fifty years ago, in a forest in Nigeria, a graduate student named Winifred Doane came across a strain of plump flies.

Doane discovered that the flies had a mutated form of a gene she called adipose. She speculated the gene helped the insects store fat to sustain them during times of famine. But it was not known how the gene worked. Researchers say the gene is present in all creatures, and could eventually be manipulated in humans to help them shed weight.

Fifty years ago, in a forest in Nigeria, a graduate student named Winifred Doane came across a strain of plump flies.

Doane discovered that the flies had a mutated form of a

Now, researchers at the University of Texas Southwestern Medical Center in Dallas have identified the adipose gene in a range of creatures - from fruit flies to tiny worms called c. elegans - and discovered they can make their test subjects retain fat cells by manipulating the gene.

Biology Professor Jonathan Graff led the research team that identified how the anti-obesity gene works.

"And if you have one form of this gene you are skinny. And if you have another form of this gene, you gain weight and are fat."

But Graff says it is not like turning a light switch on and off. He says the adipose gene is more like a volume control knob that can be turned up or down along the weight spectrum.

Graff says researchers also found the gene in mice. He says the discovery in mammals explains why humans can become obese and why it is difficult for some people to lose weight.

Graff says nature is working against them. Also, in some cases, it appears there is more than one gene contributing to the retention of fat cells in humans.

"So you have an adipose mutation that is turned down a little bit and maybe you gain a pound a year, but over 30 years that is 30 pounds. And you have its partner, and it has a mutation, you would gain one pound a year or 30 pounds over 30 years. If you have both of those at a slightly reduced function, now you could be gaining 10, 20, 30 pounds in a year."

Graff says a mutated adipose gene also produces adult onset diabetes because fat cells communicate to the rest of the body to regulate its metabolism. In diabetes, the body is unable to use glucose properly, leading to serious complications including heart disease, blindness and kidney failure.

Now that researchers have produced skinny flies and mice by altering the adipose gene, Graff says scientists could develop the technique to help people with obesity and diabetes shed fat cells, therapies that he says are still years away.

The anti-obesity gene is described in this month's issue of the journal Cell Metabolism.