Under the heading, “Research Ripe for Over-interpretation” a team of scientists from the Boston University Schools of Public Health and Medicine and the Boston Medical Center have published in the July 1, 2010 issue of the journal Science a paper identifying a suite of gene variants that can be used to predict whether people can live to 90 years and beyond. Actually, the study is quite circumspect. It was based on genome wide analysis of over 1,000 centenarians, people 100 years of age or more; and the identification of 150 significant gene segments (called single nucleotide polymorphisms or SNPs) that appear to be associated with people who live to 90 or more. At least, on superficial interpretation, that’s what the study reports. Here, in bullet-points, are other things it says:

- The 150 gene ‘markers’ were accurate in predicting longevity 77% of the time. (That’s pretty good, but obviously not perfect.)
- The oldest people, those at 110 or over, were the most likely to have the best prediction rate.
- The researchers developed new statistical techniques (Bayesian, mostly) that could be used to analyze similar gene variant patterns. (This may actually turn out to be one of the more important contributions of the study.)
- The study also analyzed the data for a correlation between the ‘longevity genes’ and the lack of gene variants associated with diseases, but found that people with longevity variants and the control group had about the same number of disease gene variants.
- The study called for specific research into how (and why) these specific SNPs are related to longevity. (That is a fuzzy area for genome-wide research. It provides interesting correlations, but the explanations will have to come much later after laborious research.)
- The presence of these gene variants does not override the importance of environmental and life-style factors in living to an old age. (If you get run over by a truck, they don’t matter. Ditto for smoking, drinking, and eating to excess.)

The authors of the study are (rightly) careful:

If these findings are confirmed, they would suggest that “predicting disease risk using disease-associated variants may be inaccurate and potentially misleading, without more information about other genetic variants that could attenuate such risk” the authors commented.
..
But they added: “This prediction is not perfect, however, and although it may improve with better knowledge of the variations in the human genome, its limitations confirm that environmental factors (e.g., lifestyle) also contribute in important ways to the ability of humans to survive to very old ages.”

Drs. Sebastiani and Perls also cautioned that they developed this genetic risk model as a way to dissect the complex genetic bases of exceptional longevity and to discover the different genetic paths to age 100 and older. An understanding of the implications of this model’s use in the general population would be necessary before this test is marketed, they said.

[Source: EurekAlert]

Will we someday (soon) ask, “You got gerontogenes?”