Y Chromosome Might Vanish One Day – Studies have shown that the Y chromosome has been at a genetic disadvantage for quite a long. It has been degenerating rapidly and has just 4.6 million years left before it disappears completely
If it’s XX, it’s a girl and if it’s XY, it will be a boy. There has existed a disparity in our fundamental genome. While women have the advantage of paired chromosomes, this couldn’t be said for men who are left with two different kinds that cannot take turns for each other. With the Y chromosome (condensed DNA) being exclusive in its very nature, it has strongly been associated with masculinity in both social and scientific communities. It has taken us a long to understand that a man and specifically his Y chromosome holds the power to determine whether a pregnant couple is going to welcome a boy or a girl. However, the conversations have turned to a different tangent altogether where research is suggesting that the Y chromosome might be dying out soon.
To recap, XX chromosomes (condensed DNA) are found in women and XY makes men.
This news can immediately put our minds wandering in different directions and we might worry about what might happen to men. Will they vanish or are we making space for a new specie? Some scientists at Hokkaido University in Japan have ensured that men aren’t going anywhere. The way the Y chromosome has vanished from a certain male species of rat has in some way given us a road map of how the same might happen with human males.
What is happening with the Y chromosome?
Studies have shown that the Y chromosome has been at a genetic disadvantage for quite a long. It has been degenerating rapidly and as per studies, just 4.6 million years are left before it disappears completely. The very fact that unlike others of its kind, the Y chromosome has no pair, is enough to show that it might fall weak before the evolutionary forces. You might have wondered why a bald father always gives birth to a son who loses his hair much like his father. The answer is simple, the faulty genes on a Y chromosome have no replacement or cannot be silenced because they have no other. It is unlike women who have two Xs and where a faulty gene on one chromosome can be silenced by a similar gene of another chromosome. In simple words, it means that the Y chromosome cannot shuffle its faulty genes with a similar partner.
Some studies have shown that over years Y chromosomes have developed some self-saving mechanisms such as making use of a copy-paste phenomenon in which damaged genes can be repaired using an undamaged backup copy. While this has been a good surviving technique but it cannot give these chromosomes a life of eternity. Science has observed that the chromosome is shrinking drastically over 200 million years of evolution.
Y chromosome has an asset gene
Studies have shown that our physical expression of male and female is not strongly bound to the X and Y chromosomes. Many of the genes that initiate those expressions are not located on these chromosomes. Studies also show that once upon a time X and Y were just like other ordinary chromosomes. So, the question is that what makes these chromosomes so gendered? The answer is a type of gene located on the Y chromosome that is working behind some important life processes like the growth of testes, the production of sperm and determining the sex of the child. The gene is SRY which works as a key switch and decides if it is going to be a girl or a boy. So when we say that we are worried about the loss of the Y chromosome, we are worried about this particular gene. Will it be lost too? This has been the cause of our worry.
Men might not be in trouble
The researchers at Hokkaido University in Japan have observed that in one of the rat species, some normal chromosomes have evolved into a new male sex chromosome. The Amami spiny rat is one such mammal that lacks a Y chromosome. Genetically, the SRY switch gene puts on other genes on other chromosomes, including SOX9 that develops testes. The team minutely examined the genome of the Y-less rats and found that a normal chromosome pair near this SOX9 has made a new copy and this also enhanced the functioning of the neighbouring SOX9. In simple words, these mice have found a replacement for the SRY switch.
Also read | Alzheimer Breakthrough: Drug Lecanemab Found To Delay Brain Cell Destruction
