The mother’s curse

This is a fascinating piece in Physorg about the likelihood that mother’s can transmit genes to their children that harm their sons but not their daughters – thanks to an evolutionary arms race between mitochondrial DNA (only transmitted by females in ova) and nuclear DNA. The article points out that, unlike the nuclear genome, which is a product, in offspring, of mother’s and father’s DNA, the mitochondrial genome is only passed on by the mother, making male offspring an evolutionary dead end. As such, it goes on to say, while natural selection actively suppresses mutations in mitochondrial DNA that might weaken females there is no pressure to weed them out of males – this leads to the mother’s curse.

The target paper for this article has been published in eLife by Maulik Patel, from Vanderbilt University, and colleagues, including some from the Fred Hutchinson Cancer Research Center in Seattle, who have discovered an mtDNA mutation in fruit flies that reduces male offspring fertility but does not affect female siblings. They believe this research substantiates the principle of the mother’s curse in animals, including humans.