July 02, 2010

New England Centenarian study

(Last Update: Jul 8)

This project has a new paper in Science. It's a strange and fascinating achievement that a test purports to guess whether you'll live to be 100 with 77% accuracy.

Becoming a centenarian is rare, and guessing the occurrence of rare events is notoriously difficult. It will be interesting to see how these results generalize to a different study population.

UPDATE (Jul 8):

Well, as I mentioned above, guessing the occurrence of rare events is notoriously difficult, and scientists that have looked at this study cast doubt on its validity. If it's too good to be true, it probably ain't. The more interesting question: how did it slip into Science?

Science DOI: 10.1126/science.1190532

Genetic Signatures of Exceptional Longevity in Humans

Paola Sebastiani

Abstract

Healthy aging is thought to reflect the combined influence of environmental factors (lifestyle choices) and genetic factors. To explore the genetic contribution, we undertook a genome-wide association study of exceptional longevity (EL) in 1055 centenarians and 1267 controls. Using these data, we built a genetic model that includes 150 single-nucleotide polymorphisms (SNPs) and found that it could predict EL with 77% accuracy in an independent set of centenarians and controls. Further in silico analysis revealed that 90% of centenarians can be grouped into 19 clusters characterized by different combinations of SNP genotypes—or genetic signatures—of varying predictive value. The different signatures, which attest to the genetic complexity of EL, correlated with differences in the prevalence and age of onset of age-associated diseases (e.g., dementia, hypertension, and cardiovascular disease) and may help dissect this complex phenotype into subphenotypes of healthy aging.

Link

1 comment:

Andrew Oh-Willeke said...

The money result, in my view is that "90% of centenarians can be grouped into 19 clusters [of the 150 SNPs] characterized by different combinations of SNP genotypes—or genetic signatures—of varying predictive value" and that supercentenarians (i.e. age 110 plus) had a large share of all of the SNPs in question.

Even if the accuracy is considerably less than 77%, this is still a huge deal. Testing for 150 SNPs is becoming something that is economic to do on a mass scale, and since the clusters appear to be cumulative in effect, one can neatly study each of the nineteen clusters separately to see what in particular is more healthy about that cluster's set of genes without worrying about headache inducing complexity in terms of interactions between the genes in the nineteen different clusters.

Getting half a dozen research groups to each look at several clusters, each characterized by a dozen SNPs to determine the genetic role of the SNPs and associated genes not tested in the biochemistry of a few score centenarians and a few hundred non-centenarians with the same genetic profiles is eminently manageable.

Moreover, even if only some of the clusters can be translated into drugs or gene therapies, a trait that adds decades to life expectancy made available via drugs or gene therapies to hundreds of millions of people worldwide, could be one of the most dramatic medical advances in history.

One can imagine the equivalent of a multi-vitamin with a cocktail of drugs mimicing the effect of these nineteen clusters of adaptations become the norm for every middle aged and older person in the world, once the patents run their course.