The Y chromosome in human men is shrinking so quickly, it could disappear altogether 鈥� though that will likely take some 4.5 million years. But the good news is that human genetics could find a solution around the problem.
The Y chromosome is the sex-determining chromosome in humans and many other animal species. It carries the 鈥渕aster switch鈥� gene, SRY, that determines whether an embryo will develop as female, with two X chromosomes, or male, with one X and one Y chromosome.
Darren Griffin, a professor of genetics at the University of Kent, explains there was once was a time when a man鈥檚 X chromosome was the same length as his Y, but that鈥檚 been changing over the last 200 million years or so.
Women鈥檚 X chromosomes haven鈥檛 changed much in the last 200 million years or so, men鈥檚 Y chromosome has been shrinking, and losing dozens of the genes it once shared with women.
So do all these changes mean that men are endangered?
鈥淭hat鈥檚 a question I get asked an awful lot, and the answer is absolutely not,鈥� Griffin told CTV鈥檚 Your Morning Wednesday. 鈥溾�� Males are not going away.鈥�
Griffin said it鈥檚 possible that the SRY gene could simply move its sex-determining mechanism to a different chromosome. That鈥檚 what has happened with Japanese spiny rats and mole voles, who lost their Y chromosomes entirely, says Griffin.
But, even if that happens to humans, it likely won鈥檛 be for several million more years.
鈥淲e鈥檙e not awfully worried. I think we鈥檝e got an awful lot of things to be worried about in the meantime,鈥� he said.
