Genetic Mutation is Key to Women’s Long Life

A mystery that has prevailed for ages about why women live on an average longer than men has finally compelled the scientists to disrupt the DNA in the power pack of the cells known as Mitochondria in order to discover a clue.

This new research describes how mutation to the DNA of the mitochondria can account for differences in the life expectancy of males and females. Mitochondria, the power pack of the cells are present in every animal cells and is very important for life as they play the vital role of converting food into energy that powers our body.

The study that was led by Monash University was published in August 2 issue of Current Biology.

The detailed study to uncover the differences in longevity and biological aging across male and female fruit flies that carried mitochondria of different origins was carried out by Dr. Damian Dowling and PhD student, Florencia Camus, both from the Monash School of Biological Sciences along with Dr David Clancy from Lancaster University.

"Intriguingly, these same mutations have no effects on patterns of aging in females. They only affect males," Dowling said. "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."

According to Dr. Dowling the results point to numerous mutations within mitochondrial DNA that affect how long males live, and the speed at which they age.

Researchers state that the mutation can be entirely attributed to a trait, the way mitochondria genes are passed down from parents to offspring.

"While children receive copies of most of their genes from both their mothers and fathers, they only receive mitochondrial genes from their mothers. This means that evolution's quality control process, known as natural selection, only screens the quality of mitochondrial genes in mothers," Dowling said. "If a mitochondrial mutation occurs that harms fathers, but has no effect on mothers, this mutation will slip through the gaze of natural selection, unnoticed. Over thousands of generations, many such mutations have accumulated that harm only males, while leaving females unscathed."

This study was based on the previous findings by Dowling that dealt with the consequences of maternal inheritance of mitochondria in causing male infertility.

Dowling concluded saying, "Together, our research shows that the mitochondria are hotspots for mutations affecting male health. What we seek to do now is investigate the genetic mechanisms that males might arm themselves with to nullify the effects of these harmful mutations and remain healthy."