Women tend to outlive men thanks to a genetic mutation passed from mother to son, a new study shows.
Scientists studied the fruit fly, which inherits mitochondrial genes only from its mother, a trait it shares with humans. They found any harmful genetic mutation in the mitochondrial DNA - passed to offspring from their mothers - would only harm male offspring and would be benign in female. This could lead to higher death rates or shorter lifespans for males.
"This means that evolution's quality control process, known as natural selection, only screens the quality of mitochondrial genes in mothers," said Dr. Damian Dowling from Monash University in Australia.
"If a mitochondrial mutation occurs that harms fathers but has no effect on mothers, that mutation will slip through natural selection, unnoticed," he added.
Mitochondria are the power generator of the cell, which combine sugar and oxygen into ATP, molecular packets of energy that are usable by cells. They also have their own unique DNA separate from the cell, coming only from the mother's egg.
The researchers expect the new findings will point the way toward treatments able to nullify the affects of mutated mitochondrial DNA. The study appears in the August 2 edition of the journal Current Biology.
For comments and feedback: editorial@rttnews.com