Just last year, researchers at the University of Copenhagen released a stunning study. What they discovered was that genetics could play an even bigger role in how long a person lives compared to what we had assumed. Doctoral student researcher Daniela Bakula and postdoctoral fellow and study leader Morten Scheibye-Knudsen. They claim that their discoveries have the potential to be transformative for the field of aging research.
The research reveals that genetics determines only around 55 percent of an individual’s life span. This represents a massive increase from previous estimates, which only considered 20 to 25 percent. Going beyond previous studies, the researchers employed complex mathematical modeling techniques. They were able to analyze more than a century’s worth of data collected from twins in Sweden and Denmark. We selected these specific countries because they are considered high standard of living countries. Their relatively uniform access to high-quality healthcare makes a fascinating context for exploring why genetics might play a role in longevity.
Professor Tony Blakely, an epidemiologist at the Melbourne School of Population and Global Health and co-author on the study, said they were exciting findings. He noted the importance of genetics while stressing that the gene has become less important than environmental influences and lifestyle choices as the critical determinants of lifespan.
“The quality of your diet, physical activity, alcohol consumption, sodium consumption, eating the fruit and vegetables, all that stuff still matters, and will be driving a lot of our own life expectancy,” – Professor Tony Blakely
Dr. Jack da Silva, an evolution expert from the University of Adelaide, praised the study for its contributions to existing research on lifespan heritability observed in other species. He noted that major genetic differences connected to longevity have already been established in classically lab organisms such as the fruit fly.
“This is an impressively thorough study. We’ve known for quite some time that there is a lot of genetic variation for lifespan in populations of organisms such as fruit flies studied in the laboratory, and that single genes can have a very large effect on lifespan in these organisms,” – Dr. Jack da Silva
The researchers hope their analysis will bring attention to these key potential, non-age-related factors that can affect mortality, and improve risk prediction. Most notably, these are accidents and infectious disease. This is an element that has been a struggle for past research campaigns. By isolating these variables, Bakula and Scheibye-Knudsen do a better job of shedding light on the role of genetics in longevity.
Professor Blakely highlighted that while environmental improvements, such as better diets and reduced smoking rates, have positively impacted life expectancy over time, genetics will always introduce variability among individuals within any population.
“That’s because of improving diets, reduced smoking, better sanitation — all those things. And so what drives how long a population lives on average is the environment. But within wherever your population is, at some point in time, there will be variability in that due to genetics,” – Professor Tony Blakely
Life expectancy Australia has witnessed a remarkable period of increasing life expectancy in the last few decades. Since 1900, it has been raised by over 30 years! As of 2023, females born in 2021-2023 can expect to live 85.1 years. Conversely, males in the same age group can generally expect to live until 81.1 years. Australia’s equally variable environment and rapidly diversifying population could add more noise to lifespan predictions, warns Blakely.
The life expectancy gap in Australia is extreme. This disparity is due to origin factors such as countries of birth, ethnic backgrounds and socioeconomic statuses of its citizens.
“In a population like Australia with different countries of birth, different ethnicities, different socioeconomic groups, you might see more variability because the environment is causing more variability, not just genes causing how long you live,” – Professor Tony Blakely
The real-world impact of this research goes beyond the ivory tower. With increasing life expectancies worldwide, understanding the interplay between genetics and environmental factors could inform public health strategies aimed at prolonging healthy lifespans.
