The study published online today in the journal Science reports on the DNA analysis of 1,055 people aged 100 or more years, and 1267 people randomly selected as control subjects, and identified several genetic markers present at a higher frequency in the centenarians.
The finding partially explains the mechanism of inheritance of exceptional-longevity in humans (i.e. the potential to reach old age of those whose parents lived longer lives), and opens the possibility for people to know if they have the potential to reach an advanced age.
Since there are many genes that are involved in a long life, the authors developed a model that calculates the probability that a person reaches an extraordinary longevity on the basis of 150 genetic markers. Using this model the researchers could predict with 77 percent of success, if a person could live to be 100 years old.
Of course, since any heritable trait is highly affected by the environment (including lifestyle, exercise, diet, consumption of alcohol and tobacco, etc.) the presence of the DNA sequences in an individual indicate the potential or genetic predisposition to realize the trait under normal situations. Thus, those lifestyle and environmental factors may explain
the 23% error rate in the predicted longevity.
"It is believed that a healthy old age reflects the combined influence of environmental factors, including choices about lifestyle, and genetic factors," says the article
The researchers, who include Paola Sebastiani and Thomas T. Perls from U. of Boston and Annibale Puca of Milan, among others collaborating in the study, separate their genetic predictions in 19 groups or sections characterized by different combinations of the markers that correlated with the potential of life beyond 100 years. Additionally, distinct patterns of markers are related to the propensity and age of onset to age-related diseases such as dementia, hypertension and cardiovascular problems.
Future studies of these genetic markers, they say in their report, could shed light on specific and different patterns of healthy aging, and ultimately may be useful for personalized medical care that takes into account the individual needs of prevention and treatment.