Is it in the genes? - National Post

Louise Levy attends regular Tai-chi classes, retired three years ago from her secretarial job and says she would still be driving today if her car had not "conked out before I did." None of which would be particularly unusual, except Mrs. Levy is 101 years old.

"My mind is still clear and I don't have a memory problem," says the resident of Rye, N.Y., about the latest chapter in a life that began when movies were silent and the Model-T Ford cutting edge. "It's been absolutely marvelous."

Mrs. Levy's long and generally healthy life is the focus of a fascinating scientific study, itself at the forefront of a little-noticed but radical approach to medical research. Turning upside down the traditional quest to understand and cure specific diseases, some researchers are examining instead healthy and long-lived humans and animals for their biological secrets.

By reverse engineering the source of that vigour, scientists hope to develop drugs or supplements that could give less genetically fortunate people more protection against the ravages of aging and chronic illness.

Those researchers struggle now for recognition in a medical establishment hived off into separate wars against individual diseases. A Canadian academic, however, is calling for a tectonic shift toward what he calls "positive biology." Solving the molecular mysteries of the healthy to stave off disease and aging would make the system "much more efficient," argues Professor Colin Farrelly of Queen's University in a recent paper in the journal of the European Molecular Biology Organization.

"We think it will be more important for public health than the introduction of antibiotics," echoed Jay Olshansky, a publichealth professor at the University of Illinois who has promoted a similar concept for several years. "This will be the medical breakthrough of the 21st century when it happens.- It's going to be huge."

Continuing to just combat specific diseases, on the other hand, will produce surprisingly modest advances, he contends. While curbing infant mortality and other achievements stretched life spans by 30 years in the 20th century, even a complete cure of all cancers would increase longevity by an average of just more than three years, Prof. Olshansky has estimated.

The argument seems to be slowly gaining some traction, with Canada's federal medicalresearch agency saying it is looking seriously at positive biology.

The study that has Mrs. Levy under a microscope is identifying genes linked to long life. Gabrielle Boulianne, a Toronto biologist, and others are unscrambling similar biological puzzles in exceptional specimens of fruit flies, worms and other lower life forms. Canadian infectious-disease experts have studied the lucky few people who seem naturally resistant to HIV infection; and a U.S. clinic is probing the DNA of diabetes patients who stay remarkably free of the disease's dire complications for decades.

At the core of positive biology is not an attempt to simply identify lifestyle choices - like quitting cigarettes or French fries - that can stave off disease, though those have proven value. The goal instead is to identify the mechanisms by which some people naturally live long and well, then translate that knowledge into pharmaceutical treatments.

The centenarian study at New York's Albert Einstein College of Medicine has enrolled more than 500 men and women who have lived in good health to 100 or close to it, focusing exclusively on Ashkenazi Jews, not because of any special aging quality, but to avoid ethnic variations that might complicate results. The Einstein researchers have come up with some intriguing findings.

Rather than all being paragons of lifestyle virtue, half the centenarians were overweight or obese, 60% smoked for over 30 years - and one had a tobacco habit that stretched across nine decades, noted Dr. Nir Barzilai, who heads the project.

"It's all genetics," he said. "To be 100 years old, it's strongly genetic."

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