ST. PAUL, Minn -- A gene variation that helps people live into their 90s and beyond also protects their memories and ability to think and learn new information, according to a study published in the December 26, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology.

The gene variant alters the cholesterol particles in the blood, making them bigger than normal. Researchers believe that smaller particles can more easily lodge themselves in blood vessel linings, leading to the fatty buildup that can cause heart attacks and strokes.

The study examined 158 people of Ashkenazi, or Eastern European, Jewish descent, who were 95 years old or older. Those who had the gene variant were twice as likely to have good brain function compared to those who did not have the gene variant. The researchers also validated these findings in a group of 124 Ashkenazi Jews who were between age 75 and 85 and found similar results.

"It's possible that this gene variant also protects against the development of Alzheimer's disease," said study author Nir Barzilai, MD, the director of the Institute for Aging Research at Albert Einstein College of Medicine in Bronx, NY.

Barzilai noted that many studies have identified risk factors associated with developing age-related diseases. "But little effort has been made to identify the reasons for longevity in exceptionally old people, and why they don't develop disease. In studying these centenarians, we hope to learn what factors lessen their risk for diseases that affect the general population at a much younger age. Our results bring us a step closer to understanding the role that genes play in longevity."

Work is being done to develop drugs that can mimic the effect of this gene variation, Barzilai said.

Approximately one in 10,000 people in the general population lives to the age of 100.