SCIENTISTS CAN now predict the likelihood of a person living to a ripe old age by looking at their genes.
But if they offered this information would you really want to know?
A Boston-based research team managed to predict with 77 per cent accuracy whether they were looking at a person with genes that would carry them through to reach 100 years or a person unlikely to receive the President’s centenarian cheque.
As usual it all comes down to your genetic make-up, whether you are lucky enough to possess a collection of up to 150 so-called Methuselah genes.
Researchers from Boston University and the Boston Medical Centre studied the genes of more than 1,000 centenarians, people who saw in their 100th birthday.
They then compared these long-lived genes against genes from younger “controls” whose longevity still remains a mystery.
The object was to find any variations or “genetic signatures” common in the older group that were not present in the control group, explained co-lead researcher Prof Paola Sebastiani whose findings with Prof Thomas Perls were released online yesterday by the journal Science.
They found no fewer than 150 of these genetic signatures that were commonplace in the centenarians.
They then used these Methuselah genes to predict if a person survived to very old age and managed to do this with up to 77 per cent accuracy. Their study “shows that genetic data can indeed predict exceptional longevity without knowledge of any other risk factor”, the researchers write.
They also found that the older you were the more likely you were to have many of these longevity genes. They found that 45 per cent of the oldest centenarians, those who had reached 110 and more, had the highest proportion of these Methuselah genes.
The researchers believe that if this can be done for longevity it can be done with many other conditions. “The methodology that we developed can be applied to other complex genetic traits, including Alzheimer’s disease, Parkinson’s, cardiovascular disease and diabetes,” Dr Sebastiani said.
Their findings, however, have also confused the issue about whether a simple study of a person’s genes can give a prediction about susceptibility to a given disease. Many international groups have identified susceptibility genes for a range of common diseases. The team decided to look for these in their centenarians and the controls.
The researchers found, however, that there was little difference between the two groups, the older subjects had just as many disease-related genes as the controls.
This surprise finding must be confirmed by subsequent studies, but it suggested that predicting the risk of disease by looking at telltale genes “may be inaccurate and potentially misleading”, they said.
With this in mind the researchers struggled to understand why centenarians and controls had a similar number of disease genes. They suggested that the longevity genes must be able to counter the effect of the disease-related genes, holding the bad genes in check and allowing the person to live a long, healthy life.
The fact that they could only achieve a 77 per cent accuracy was explained away by the scientists. Their predictions were not perfect and they might improve over time, but lifestyle choices and environmental factors will also influence longevity.