The topic is exceptional longevity, and can we predict it. This is an outgrowth of the Science paper by Sebastiani and colleagues, including Thomas Perls from Boston University, [published] July 1st in Science. This paper has been responsible for generating quite a controversy, which we will get into in a minute. Basically, the main finding for looking at a large group of centenarians that the New England group has accumulated over many years and doing a genome wide association study compared to a potpourri of controls --controls that came from the Illumina database, controls that included children of parents who had died in their 70s, and even a group of Parkinson’s disease patients -- so this was one of the concerns. Another one that was raised in the post-publication phase was the problem with the chips. That is, there were different chips that were tested, one that looked at 310,000 SNPs and another one that looked at 670,000 SNPs. These were not used in all the patients, so there was some lack of potential quality control regarding the SNP markers. Nonetheless, what this group concluded in Science was that using 150 SNPs, one could predict with 77% accuracy whether you would live to centenarian status, which is a pretty big jump, of course, for not only today. It is very difficult to predict longevity. Now this has come under siege. There have been reports in the New York Times. There was a Newsweek article that was entitled “The Little Flaw in Longevity-Gene Study That Could Be a Big Problem.” There are all sorts of things in the blogosphere such as “Serious Flaws Revealed in ‘Longevity Gene’ Study” [by Daniel MacArthur]. The critical issue, though, is whether these data will hold up to reanalysis. The investigators will have to redo the model that predicts exceptional longevity, taking out the SNPs that are now known to be faulty, and see whether or not, with the replication that they had, it will all hold up. Probably there will be some dilution of the effect, but some of the genes that came out of this study like TOM40, which is a known major modulator of the APOE locus adjacent to this gene, and which has already been implicated in longevity, itself were quite striking. So, we will have to see what this will turn out. This is quite a controversial study. Longevity and the science of aging is an area of fascination, and I would be interested to get your thoughts. What was really striking was that a Wall Street Journal poll that was conducted in the days after the Science paper asked how many people would like to know whether they carry the gene markers for exceptional longevity, and 75%of people (who at least read the Wall Street Journal and go onto its website and vote) wanted to get this information.
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