Scientists from Stanford and elsewhere have been hunting for a genetic explanation for extreme longevity for the past four years and are realizing that it is a more difficult proposition than they initially hoped.
Their research compared the genomes of 17 "supercentenarians" - those who have lived 110 years and beyond - with those of 4,300 "regular" people recorded earlier in a National Institutes of Health study. The study was geared toward finding a single gene or group of genes responsible for a particular trait - in this case longevity - similar to genes which have been found to cause disease or confer immunity. But they have had no luck. Stuart Kim, PhD, a Stanford geneticist and molecular biologist and founder of the Kim Lab for the study of aging, commented in a San Francisco Chronicle piece:
We were looking for a really simple explanation in a single gene, and we know now that it’s a lot more complicated, and it will take a lot more experiments and a lot more data from the genes of more supercentenarians to find out just what might account for their ages.
However, data about the oldest people in the world still suggests that the reason they can live so long has to do with their genes, and not with lifestyle choices. The supercentenarians have average rates of cancer, heart disease, and stroke, although they have escaped many age-related diseases, and their smoking, alcohol, exercise and diet appear no different than among ordinary people. Furthermore, as noted in the article, the parents, siblings and children of the centenarians have also lived well beyond average.