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Fear Arises As Research Reveals Human Male Specie May Be Extinct In Some Years

There are fears that men may become really scarce soon as the male-determining Y chromosome could be dying out, with far fewer genes than the X and research suggests it’s gradually shrinking.

Ideally, a person’s sex is determined by whether they have two X chromosomes (which causes ovaries to develop) or an X and a Y (which results in testes).

Approximately, X chromosomes have 1,000 genes, while Y has just 45 and research suggests the Y chromosome is really shrinking.

Genes develop mutations over time, some of which are harmful. Chromosome can avoid passing on such harmful mutations by mixing and matching with each other during meiosis — the stage of foetal development during which our forming bodies develop sperm or eggs.

This process breaks up the genes and makes it more likely that only strong, non-harmful ones get passed on.

But, only X chromosomes can swap with each other, as Y isn’t similar enough to combine.

Due to the fact that  individuals don’t (generally) have two Y chromosomes, Y can’t recombine with itself.

Therefore, over millions of years of evolution the Y chromosomes shrink.

Research conducted by Jennifer Graves, a geneticist at La Trobe University in Melbourne, suggests that 166 million years ago the Y chromosome had a similar number of genes as X, approximately 1,669.

“So it doesn’t take a great brain to realise that if the rate of loss is uniform —10 genes per million years — and we’ve only got 45 left, the whole Y will disappear in 4.5 million years,” she told Live Science.

However, losing the Y chromosome completely is still a possibility, as it has proved in other species, which includes underground rodents known as mole voles, as well as certain species of spiny rats in Japan.

This doesn’t necessarily mean that men are doomed, as the loss of the Y chromosome doesn’t erase the male sex from a species as both spiny rats and mole voles still have males and females.

Rasmus Nielsen, a geneticist at the University of California, Berkeley said “People think that sex is sort of a very determined thing,”.

That if you have a Y chromosome, then you’re a man, or you don’t have [a] Y chromosome, then you’re female. But it doesn’t work like that.”

“In truth, 95% of genes that are expressed differently between males and females don’t actually live on the X and Y chromosomes.

“Losing the Y chromosome doesn’t mean losing the male,” Nielsen explained.

If the Y chromosome was to vanish, another gene would likely take over as the main determinant of sex during human development.

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