Bizarre it may appear, but having two mothers may be the key to a longer lifespan - in mice, at least, a new study has revealed.
Scientists in Japan have discovered that mice with two biological mothers but no father live about 30 per cent longer than usual, in a pioneering experiment which they claim could have implications for understanding human ageing.
While it is not yet known whether the effect applies to humans also, the research gives new insights into genetic influences on the ageing process in mammals which might be eventually exploited to slow it down, ‘The Times’ reported.
It could also illuminate the way that genes provided by mothers and fathers combine in the embryo, improving understanding of reproduction and certain diseases, according to the scientists.
Professor Tomohiro Kono of the Tokyo University of Agriculture, who led the research, said that it could even offer clues to why women typically live longer than men.
“The study may give an answer to the fundamental questions: that is, whether longevity in mammals is controlled by the genome composition of only one or both parents and, just maybe, why women are at an advantage over men with regard to the lifespan,” he was quoted as saying.
For the experiment, the scientists created 13 “bimaternal” (BM) mice, conceived from two eggs, and compared these with 13 female mice of the same strain produced in the normal fashion and raised in the same environment.
The study found that the BM mice lived on average for 186 days longer than the normal animals, an increase which was equivalent to a group of women living to an average age of 105, compared with the current average of 81.
The longer-lived BM mice were significantly smaller and lighter than the normal ones.
Prof Kono said that the increased life-spans of the BM mice probably reflected the abnormal way in which their genomes were imprinted, as they had no DNA of male origin.
This suggests that certain imprinted genes from the father’s sperm may suppress lifespan, perhaps while also increasing body size, the scientists said.
The findings have been published in the latest edition of the ‘Human Reproduction’ journal.