Although no one can predict how long they will live, factors like genetics, lifestyle, gender, and ethnicity can impact a person’s longevity.

Now researchers from École Polytechnique Fédérale de Lausanne in Switzerland have discovered specific gender- and age-dependent genes linked to longevity through a large-scale mouse model.

For many years, scientists have studied which gender lives the longest: women or men. Past research shows that women live longer than men in most parts of the world. A recent study also suggests that women who are physically active may live longer regardless of their genes.

The Centers for Disease Control and Prevention (CDC) estimate life expectancy for women in the United States at about 79 years compared to about 73 years for men. Some reasons why men may have a lower life expectancy than women include: higher rate of occupational injury and death, less likely to go to the doctor, higher risk for cardiovascular disease, increased suicide risk, more likely to drink excessive amounts of alcohol.

Although women may live longer than men, research shows women are more susceptible to certain diseases than men, which could ultimately affect their lifespan and quality of life. These include stroke, depression, Alzheimer’s disease and autoimmune disease like multiple sclerosis and rheumatoid arthritis.

This study used a large-scale model featuring more than 3,000 genetically-diverse mice. The research team identified specific genetic loci – the physical location of a specific gene on a chromosome – correlated to longevity.

Additionally, researchers found some of these specific genes were different depending on if the mouse was male or female. Additionally, some genes did not affect lifespan until a mouse reached a certain age. This was specifically observed in male mice.

According to Dr Maroun Bou Sleiman, a scientist at the Laboratory of Integrative Systems Physiology at École Polytechnique Fédérale de Lausanne and the lead author of this study, he was not surprised to find distinct genetic loci determined that male and female longevity.

“First, this has been shown in other species, notably Drosophila melanogaster,” he said. “Second, male and female mortalities are different – females live longer than males, (and) males have a wave of early deaths due to stresses associated with (a) dominance hierarchy.”

“Third, the life history of males and females is different as well as their immunity, endocrinology and metabolism,” Dr Bou Sleiman continued. “Finally, many of the interventions that extend lifespan in mice do that in a sex-specific manner. There is, therefore, a necessity to systematically assess traits such as longevity in each sex separately.”

Also through the study, Dr Bou Sleiman and his team discovered some overlap between the longevity genetic loci and specific genes related to body weight and growth. And researchers also found that early-life nutrition quality played an important role in how long a mouse lived.

“Longevity is one of the most complex phenotypes, as it is the final outcome of very many interdependent processes or components, some of which may have a larger impact (on) one of the sexes. It is, therefore, no surprise that genetic effects on different processes would lead to different longevity outcomes,” Dr Bou Sleiman

Considering body weight and nutrition are modifiable factors, might this urge discussion between medical professionals and patients on improving a person’s longevity? Dr Bou Sleiman said no – the real focus should shift from lifespan to health span or how long a person lives free from disease.

“It is plausible that lifespan and healthspan share some common genetic components, and therefore knowledge about one would inform about the other,” he explained.

“The scientific community will have to work hard on understanding the [relationship] between early nutrition, growth, health and longevity before reaching new guidelines and recommendations for ‘optimal’ growth,” Dr Bou Sleiman added. “Maybe one day, we may have personalised recommendations that would be informed by genetics.”

Medical News Today also spoke with Dr Scott Kaiser, a geriatrician and Director of Geriatric Cognitive Health for the Pacific Neuroscience Institute at Providence Saint John’s Health Center in Santa Monica, California. Dr Kaiser said while it is a “very interesting study” that “reinforces the notion that longevity is really complicated,” it is important to remember this is still a mouse study.

“It’s a long way from a laboratory mouse model to actual real life in people and unlocking the secrets of human longevity,” Dr Kaiser explained. “But these are all important steps – it’s all part of the journey. Digging in to better understand sex differences in animal models across different species is critical work.”

“This kind of work could really yield key biologic insights, but also can be an important step in terms of informing drug discovery, which could ultimately lead to new treatments, which could help people not just live longer, but live better in terms of having more years where they are vibrant, active, engaged, and free of disease,” says Dr Kaiser.

Dr Kaiser agrees there are key connections between nutrition, physical activity and longevity.

“Absolutely C,” he continued. “That shouldn’t come as a surprise – if anything that should just encourage people to focus more on healthy nutrition across their lifespan.”

However, Dr Kaiser stresses people should not think that it’s too late to make any changes because this study refers to early-life nutrition.

“All this substantiates the idea that certainly it’s never too early to be thinking about the things that can help you live well and age well,” he explained. “It’s really never too late to do something that could positively impact your quality of life and your lifespan. At the end of the day, the most important thing we can do now is still really focus on the behaviours that we know can positively influence how long we live, like eating a healthy diet (and) exercising regularly.”

“Prioritising healthy relationships because we know loneliness and social isolation are associated with premature mortality. Focusing on living a full life and having a strong sense of purpose. Sleeping well, not smoking – these are all things we know can influence how long we live and how well we live. People need to focus on that (and) this should encourage people to continue to focus on that,” Dr Kaiser added.

• A Medical News Today report