An ambitious plan to sequence 100 genes in 1,000 healthy old
people could shed light on genetic variations that insulate some people from the
ailments of aging, including heart disease, cancer, and diabetes, allowing them
to live a healthy life into their eighties and beyond. Rather than focusing on
genetic variations that increase risk for disease, scientists plan to focus on
genes that have previously been linked to health and longevity.
In recent years, advances
in genetic screening technologies have allowed scientists to start searching the genome for clues to healthy aging and a lengthy
life span. That work has revealed that the genomes of healthy old people are not
blemish free. "These people have genetic susceptibility markers for many serious
diseases, including cardiovascular disease, stroke, and diabetes, but they don't
get any of these diseases," says Eric Topol, a cardiologist and head of the Genomic Medicine
Program at the Scripps Translational Science Institute, in La Jolla, CA, who is
leading the project. "What is the explanation? What might account for their
insulation from these diseases?"
To answer that question, researchers are collecting blood
samples from 1,000 people age 80 or older who have never suffered any serious
illnesses and do not take medication. They plan to sequence 100 genes, known
from animal research and other studies to influence health and aging. "We are
especially interested in major housekeeping, master-control genes like [those
involved in] DNA repair or insulin growth factor-1," a protein hormone involved
in cell growth, says Topol. Enzymes involved in DNA repair are of interest in
longevity research because cells often accumulate mistakes in their DNA sequence
with age, and defects in some mouse and human DNArepairgenes trigger what looks like premature aging. The
receptor for insulin growth factor-1 (IGF1) has been shown to affect aging in
mice, nematodes, and flies. Read More...