Human evolution remains a tricky area for scientists to study, it takes thousands of years and large sample sizes to understand just where our genes have taken us. One of the most startling new findings that put this into play was a recent discovery by Columbia University where 215,000 people across the United Kingdom and the United States had their genes analysed for one simple reason. To see what genes affect longevity?
The two culprits were APOE, which is linked to Alzheimer’s, and CHRNA3, which is associated with a predisposition to smoking habits in men.
Surprisingly in the study, it showed that the mutations decreased sharply as the participants got older and that both mutations appeared more prevalently in younger people proving that natural selection is getting rid of harmful genetic mutations that shorten people’s lives.
To identify which bits of the human genome might be evolving, researchers looked at mutations whose prevalence changed across different age groups. For each person, the parents’ age of death was recorded as a measure of longevity or their own age in some cases. As Hakhamanesh Mostafavi, an evolutionary biologist at Columbia University in New York City confirmed, “If a genetic variant influences survival, its frequency should change with the age of the surviving individuals,”.
Diverse results also appeared such as groups of harmful genetic mutations that are usually responsible for predisposition to asthma, high body mass index and high cholesterol, all were not found prevalent in people who lived longer. Genetic markers that were responsible for late puberty and childbearing were also found to be visible in people with longevity. Which suggests that people with high levels of wealth and education tend to usually live longer allowing for more opportunities later in life to reproduce.
Insights into our evolution and genetic makeup are happening all the time, but we’re realising slowly that our genetic makeup is not so different, in fact, odds are constantly diminishing as to our differences from others. One of the most high-profile discoveries that we learned was back in 2008, where scientists found that 6,000 to 10,000 years ago a genetic mutation allowed for the first set of blue eyes to appear. Our genetics make up who we are, and identifying what they do gives us power over where we’re heading. But the key question now is are we transitioning now to a point where the area of genomics takes over and we can edit the type of future we all want?