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‘Greedy gene’ discovered by scientists
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Shine On
It's being called both the "gluttony gene" and the "greedy gene": Scientists have discovered a genetic reason why some of us can't get enough food — even when we're full.
In tests on mice, researchers at Georgetown Medical Center found that a mutation on the Bdnf gene led to non-stop eating and weight gain by breaking down communication in the body.
Read the full article, published in Nature Medicine, here.
Humans also have these genes. Scientists have long speculated that it plays a role in obesity, but are only now discovering how it works.
Here's what they know so far:
After we eat, the gene transmits chemical signals down a chain of brain cells. Eventually, that signal reaches the hypothalamus. The hypothalamus receives the message, understands that you're full, and then suppresses your appetite.
The tests on mice found, however, that if that particular Bdnf gene has a mutation, the chemicals — insulin and leptin — fail to reach their target, causing the mice to eat twice as much as their counterparts without the mutation.
[See also: Why you're never too full for dessert]
"If there is a problem with the Bdnf gene, neurons can't talk to each other, and the leptin and insulin signals are ineffective and the appetite is not modified," said lead researcher Dr. Baoki Xu.
"This discovery may open up novel strategies to help the brain control body weight."
Xu's research team found that the Bndf gene has two versions — long and short, or "truncated" — which develop in the womb. Those born with "long" genes have successful chemical communication, with the hypothalamus being told "I'm full." Those born with the shorter form, however, don't have all the chemical signals picked up by the branch-like dendrites that ensure proper communication in the body.
Scientists now hope to determine whether or not Bndf correction is possible.
"The better approach might be to find a drug that can stimulate Bdnf expression in the hypothalamus," Xu says.
"We have opened the door to both new avenues in basic research and clinical therapies, which is very exciting."
When you overeat, do you blame your genes?
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