The Y chromosome, which determines the development of sexual characteristics in men, will disappear after about a few million years. Geneticist Darren Griffin from the University of Kent (England) writes about this in an article published in Science Alert. A number of researchers believe that this is inevitable, although there are genetic mechanisms that inhibit the process of degeneration.
The male chromosome contains genes that are not essential for life. Among them is the SRY gene, which determines the development of the body in the male pattern. They do not have additional copies, recombination with which could prevent the permanent loss of Y-chromosomal DNA functions due to mutations. Over the entire history of the existence of life, the chromosome has strongly degenerated, and this process will continue, according to scientists, for another 4.6 million years. This will inevitably be accompanied by impaired fertility.
Degeneration is slowed down by such phenomena as large-scale chromosomal rearrangements, leading to the appearance of additional copies of genes on the Y chromosome. This is influenced by the presence of palindromes - sequences of nucleotides that are read equally in both directions. It is known that in the area of palindromes it is easier to copy and paste DNA sections. Gene copying helps maintain sperm function.
At the same time, the degeneration of the Y chromosome does not mean the complete disappearance of men. The SRY gene can move to another chromosome, which, however, will also begin to lack recombination.
