Scientists say they can predict whether someone may live or die longer than average by looking at their DNA. The team analyzed the combined effect of genetic variations affecting lifespan to produce a scoring system. People who score in the top ten percent of the population may live five years longer than those who score in the bottom ten percent, they say. The findings also revealed new insights into diseases and the biological mechanisms involved in aging, the researchers say.
The researchers looked at genetic data from more than half a million people, as well as data on the lifespan of their parents. About 12 regions of the human genome were considered significant for lifespan, including five locations not previously reported.
The DNA sites with the greatest impact on overall longevity were those previously associated with fatal diseases, including heart disease and smoking-related conditions. However, genes associated with other cancers, not directly associated with smoking, did not appear in this study. This suggests that the susceptibility to death caused by these cancers is due to rarer genetic differences in affected people, or to social and environmental factors.
The researchers had hoped to discover genes that directly affect how quickly people age. They say that if such genes existed, their effects were too small to be detected in this study.
The researcher said:"We have found genes that affect the brain and the heart is responsible for the most variation in lifespan."
