Scientists: Mother’s Curse reason why women live longer
After years of speculation, scientific evidence has finally surfaced to debunk the myth of why women tend to live longer than men and it all has to do with what scientists call “Mother’s Curse.”
The State of World Population 2011 Report: People and Possibilities in a World of 7 billion found that in Kenya, just like in many other parts of the world, women tend to outlive men by several years.
According to the report, Kenyan women live for as many as 59 years in terms of the national life expectancy while men have theirs shortened to 57 years. The situation is rather similar for neighboring Tanzania where it was found that men there have two years shorter to live than their female counterparts.
In a report published on Current Biology and released online Thursday by scientists from Lancaster University and Monash University in Australia, a DNA transferred from mother to child during the paring of chromosomes in a process that forms the foetus is responsible for why women tend to live longer.
Scientists involved in the study established that harmful genetic mutations occur because of this transfer, accumulating to cause speedy aging in men and not women in a natural selection process dubbed the mother’s curse.
“All animals possess mitochondria, and the tendency for females to outlive males is common to many different species. Our results therefore suggest that the mitochondrial mutations we have uncovered will generally cause faster male aging across the animal kingdom,” Said one of the lead researchers, Dr. Damian Dowling.
The reason advanced as to why the genes are not harmful to females but harmful to males has everything to do with natural selection process. In the plain scientific sense of it, a harmful gene is normally filtered out by natural selection by ensuring harmful mutations are not passed down from a mother to her offspring.
However, in this case, the harmful mutations could not be prevented from being passed down to the offspring since only males are affected and not females, hence natural selection sees it as not harmful.
“If a mitochondrial mutation pops up that is benign in females, or a mutation pops up that is beneficial to females, this mutation will slip through the gates of natural selection and go through to the next generation,” Dowling told Livescience.
According to Livescience, “Mother’s Curse” was tested in fruit flies but Dowling confirmed that genetic inheritance of mitochondrial DNA is the same across species, so he’d expect to see the same results in human males.
Previous myths which existed in many cultures suggested that the difference in longevity between men and women was associated with men’s inherent nature to take lethal risks but this latest finding makes a challenge to this and other theories by backing the facts with scientific evidence.