How does the Y chromosome determine human sex?
In humans, as in other mammals, females have two X chromosomes, while males have an X and a smaller Y chromosome. The X chromosome contains about 900 genes unrelated to sex, while the Y contains about 55 genes and a large number of non-coding DNA.
Y chromosome is lost
Jenny Graves, Professor of Genetics from La Trobe University in Australia, is one of the scientists who revealed that humans will lose their Y chromosome. “So, if someone visits Earth 11 million years from now, they may not find any humans,” Graves wrote in The Conversation. Or he may encounter several different types of people kept apart by different gender determination systems.”
On the other hand, a team led by Hokkaido University biologist Asato Kuroiwa discovered that most of the genes on the spiny mice Y chromosome had been moved to other chromosomes, but found no trace of either SRY or its replacement gene.
In the latest study of Kuroiwa and his team, gene sequences that are not found in female chromosomes but only seen in males’ chromosomes were detected. It is stated that these genes may be the genes that determine the sex.
Graves states that the human Y chromosome, which started to disappear as a result of all this, may gain a similar ability in the future. Graves also said, “…However, the evolution of a new sex-determining gene comes with risks. What if more than one new system develops in different parts of the world?” used expressions.