Scientists have produced a longevity scoring system to predict whether a person can expect to live longer or die sooner than average, based on the cumulative effect of genetic variants that influence lifespan.
The findings suggest that a simple genetic test could be used as an indicator of life expectancy. The researchers believe that their current findings could already be incorporated into private DNA tests to predict lifespan for as little as £150.
'We found genes that affect the brain and the heart are responsible for most of the variation in lifespan,' said study author Paul Timmers, a PhD student at the University of Edinburgh's Usher Institute.
The study analysed genetic data from more than half a million individuals. By comparing this data to records of each participant's parental lifespan, the team aimed to locate regions of the genome that might be associated with longevity.
A lifespan score was allocated to an individual based on the combined data from each of these genomic regions. Participants were then grouped together based on their projected longevity.
'If we take 100 people at birth, or later, and use our lifespan score to divide them into ten groups, the top group will live five years longer than the bottom on average,” said Dr Peter Joshi, who led the study at the Usher Institute.
The study, published in eLife, identified a total of 12 areas of the genome that appeared to have a significant impact on lifespan. This included five sites that had not been previously associated with ageing. However, the sites with the greatest impact on overall health were those that had already been linked to fatal illnesses – including heart disease and smoking-related conditions.
A myriad of genetic, behavioural and environmental factors are implicated in lifespan. Nonetheless, the researchers had hoped to uncover individual genes that directly influence the rate of ageing, beyond disease risk. If such genes exist, their effects were too small to be identified in this study.