THE VIRGINIAN-PILOT
Copyright (c) 1994, Landmark Communications, Inc.
DATE: Thursday, December 1, 1994 TAG: 9412010480
SECTION: FRONT PAGE: A1 EDITION: FINAL
SOURCE: BY JOHN SCHWARTZ, THE WASHINGTON POST
DATELINE: NEW YORK LENGTH: Medium: 61 lines
Is being fat mainly in the genes?
Researchers Wednesday announced the discovery of a gene in mice that causes obesity when it malfunctions - and they have found a probable counterpart in humans.
The discovery could lead to new weight-control treatments and has profound implications for obesity research, said Philip Gordon, head of the division of the National Institutes of Health that helped fund the study.
The researchers, led by Jeffrey M. Friedman of the Howard Hughes Medical Institute at Rockefeller University in New York, published their findings in this week's issue of the journal Nature.
The researchers believe that the gene, called ``ob,'' regulates the amount of fat in the body, by making fat cells secrete a protein that signals when the body has enough fat. The brain - and perhaps other organs - are thought to respond to the signal by suppressing appetite or altering energy metabolism.
Mice with a defective copy of the gene do not produce the protein. No one knows what percentage of obesity in humans might be caused by the gene. But Gordon said that if the same mechanism operates in some overweight people, it would put them at the center of a vicious cycle.
``Your brain doesn't get the signal'' that the body has enough fat stored up for good health, he said. ``The brain never knows, essentially, when you're satiated.''
Researchers suggested the discovery could lead to a new treatment of obesity. Using genetically engineered bacteria, scientists could produce the protein in bulk and administer it to people whose obesity is caused genetically, reducing the craving for food.
Such a drug, like insulin, would allow doctors to intervene in and correct the body's natural regulatory processes. It might even help in treating ``wasting'' symptoms in such diseases as AIDS and cancer, the researchers said.
But researchers warned that such a treatment is years away - 10 years, by some estimates - and would only be possible after a series of scientific discoveries.
Sally Smith, president of the National Association to Advance Fat Acceptance, said that the findings confirm the position of her group, which contends that obesity often cannot - and should not - be controlled by dieting.
But Smith said she worried that, ``instead of saying `Oh, now we understand,' '' the society will instead characterize obesity ``as a genetic defect requiring correction.''
Though not every overweight person is unhealthy, excessive weight can cause significant health problems such as type II diabetes, high blood pressure and some cancers. By some estimates, more than three in 10 adult Americans weigh at least 20 percent more than their ideal body weight.
Research cited by the Rockefeller team indicates that 60 percent to 90 percent of the variability in people's weights can be attributed to genetic factors. by CNB