Analyzing human genetics uncovers clues to longevity
Japanese researchers looked into the genome of 676,000 individuals and found the strongest risk factors in reducing our generation's lifespan: high blood pressure and obesitySvisio | iStock.com
By Tiffany Chen
Embedded in DNA, our genes determine biological traits from eye color and blood type to the risk of diseases. Now, in a study published March 23 in Nature Medicine, Japanese researchers discovered that individuals who have a genetic susceptibility to high blood pressure or obesity have a shorter lifespan.
“The genetic code contains a lot of information, most of it of unknown significance to us,” says senior author Yukinori Okada of Osaka University in a press release. “The goal of our study was to understand how we can utilize genetic information to discover risk factors for important health outcomes that we can directly influence as health care professionals.”
Like many diseases, the length of our lifespan is polygenic, involving many different genetic constitutions. Instead of assessing the impact of the genes one by one, Okada’s team looked at biobank data from Japan, the UK, and Finland, which includes 675,898 individuals with different ethnicity. From the biobank’s DNA samples and clinical data, the researchers can calculate an individual’s risk of having a reduced lifespan based on one’s genetic composition.
The researchers found the two most substantial risk factors that reduced the lifespan of our generation: high blood pressure and obesity. While high blood pressure decreased lifespan across all populations in the biobank, obesity showed a distinct effect on ethnicity. Obese European individuals have a higher mortality rate than East Asian individuals. The team suggested that somehow, the Japanese population was protected from the adverse effects that obesity has on lifespan, and the phenomenon warrants more trans-ethnic studies.
“Biobanks are an incredible resource,” says first author Saori Sakaue of Osaka University in the press release. “By collaborating with large biobanks in the UK, Finland, and Japan, we not only had access to large amounts of data but also to genetically diverse populations, both of which are necessary to make clinically meaningful conclusions.”
Biobanks that collect biological data, medical data, and tissue samples across different populations have provided scientists guidance and clues as to where to look. However, biobanks don’t have a universal standard in data collection, which may cause bias along with other statistical limitations. The team called for a larger number of mortality records with a longer follow-up period for an opportunity to further validate the study’s results in the future.
“These are striking results that show how genetics can be used to predict health risks,” says Okada in the press release. “Our findings could offer an approach to utilize genetic information to seek out health risk factors with the goal of providing targeted lifestyle changes and medical treatment. Ultimately, these approaches would be expected to improve the health of the overall population.”