Follow for more talkers

Why men could vanish from planet Earth

An award winning geneticist claimed two decades ago our Y chromosome will eventually go.

Avatar photo

Published

on
friendship, diversity, ethnicity and people concept - international group of happy smiling men over white
(Ground Picture via Shutterstock)

By Mark Waghorn via SWNS

Men could vanish from planet Earth scientists fear after the discovery that an endangered rat lacks the male chromosome.

The same is happening to humans as the Y chromosome has been shrinking meaning eventually it could disappear, ending the male gender.

Lead author Professor Asato Kuroiwa said: "The Y chromosomes in many mammals, including us, have been shrinking over tens of millions of years - and could eventually disappear."

The endangered spiny rat lives on the Japanese island of Amami Oshima. Only a few remain.

Kuroiwa, of Hokkaido University, said: "There is no reason to think our Y chromosome is any more robust than the spiny rat’s."

A child's gender is determined by chromosomes - known as X and Y. They carry our DNA. Males have XY while females have XX.

Fathers contribute the X or Y, and mothers an X. Inherit an X and Y and you are a boy. Get a pair of Xs and you are a girl.

An award winning geneticist claimed two decades ago our Y chromosome will eventually go.

Proffesor Jenny Graves, of La Trobe University, Melbourne, told New Scientist: "I think this latest piece of work is brilliant. The evidence is very compelling."

It is believed a mixed population of males with and without a Y was present on the island within the last two million years.

Then most individuals died off, probably as a result of rising seas, leaving only males with no Y.

Kuroiwa said: "At some point in the past, the sea level rose and the land area was much smaller."

Experiments showed the species has only managed to survive by evolving a 'proto-Y' chromosome.

Since the dawn of humanity, men have played a vital role in determining the sex of their offspring.

The Y chromosome is carried by roughly half of a man's sperm. It dictates whether a child will be male or female.

If the Y chromosome is present, a child will develop into a boy, whereas a lack of this strand of DNA will result in a girl.

Kuroiwa said: "I absolutely agree with Jenny. I also believe the Y chromosome will disappear."

Both sexes in the spiny rat now have only a single X chromosome. And this could also be lost over time.

"Since it is unstable and mutations are accumulating, I think X will eventually disappear," Kuroiwa said.

It is hoped proto-X and proto-Y chromosomes will eventually become distinct and save the animal from extinction.

The study is published in Proceedings of the National Academy of Sciences.

Stories and infographics by ‘Talker Research’ are available to download & ready to use. Stories and videos by ‘Talker News’ are managed by SWNS. To license content for editorial or commercial use and to see the full scope of SWNS content, please email [email protected] or submit an inquiry via our contact form.

Top Talkers