Is there a scientific reason for why women tend to live a longer life than men?
Research has shown that women often live longer than men, on average, and many other mammals show a similar pattern.
While the exact reason for this pattern has not yet been determined, a recent study done by researchers from the University of California, San Francisco offer a new potential explanation.
Why Might Women Live Longer?
When it comes to genetics, most women have two X chromosomes and most men have one X and one Y chromosome. The X chromosome contains hundreds of protein-encoding genes. The Y chromosome carries the gene that determine the male traits, such as testes.
This new study has found that the XX chromosomal pairing is comprised of genetic material that can extend lifespan. However, this is only when in the presence of corresponding female hormones that the ovaries produce.
Dr. Dena Dubal claims that, “ One can imagine nature has driven females to evolve this way. When you’re living longer, you can really ensure the well-being of your offspring and maybe even their offspring.” Which leads to the idea that women might live longer due to a inert motherly instinct driving them towards a longer lifespan.
Research With Mice
The study used a mouse model to explore what might give females this advantage when it comes to longevity.
The mice were genetically engineered to belong to one of four categories. The four categories were: XX chromosomes and developed ovaries, XY chromosomes and developed testes, XX chromosomes and testes, or XY chromosomes and ovaries. The first of the two groups were developed to represent what would usually happen in nature.
Researchers found that all of the mice that had the XX chromosomal pairing survived longer than those with XY chromosomes. This was apparent for both groups of XX chromosomes with ovaries or testes.
However, when they looked further into the longevity and enjoyment of their lives, it was the mice with both XX chromosomes and ovaries that enjoyed a truly prolonged lifespan, compared to the mice with XX chromosomes and testes.
This may be due to the hormones produced by the ovaries with XX chromosomes that are activating biological pathways or development throughout life.
The study noticed that the mice with the XX chromosomes measured a longer lifespan than the 21- month life mice typically live. It was found that the mice that had XX chromosomes escaped early death as they aged unlike the XY chromosome groups.
There are still many things left to determine when it comes to why the second X chromosome can decrease mortality within aging. Previous studies have found that in females, one X chromosome in every cell is randomly deactivated. This may provide some link as to why the XX chromosome is so special.
This may be a link to women’s longevity because if the active X chromosome becomes damaged, the inactive X can step in and take over.
This link leaves the need to investigate this theory further in order to truly understand why women have a longer lifespan than their male counterparts.