In humans and other mammals, the Y chromosome genes determine the male sex of the child. A recently published research has found that the Y chromosome is gradually declining. Research has found that the Y chromosome is gradually decreasing and a time will come when it will be completely gone. The results of this research have raised concerns about the future of human reproduction and it is possible that a time will come when only girls will be born in the whole world. This danger will remain until a new sex-determining gene is developed.
The decline in the male chromosome has created deep concern among scientists about the existence of the human race. However, in the meantime, a research paper published in ‘Proceedings of the National Academy of Sciences’ has also brought some good news. It was observed that two species of mice lost their Y chromosome, yet they have been successful in saving their species.
The research paper has revealed that a species of mice (spiny mice) had already developed a new chromosome before the Y chromosome vanished which is necessary for the birth of male mice. Scientists are relieved by this research paper that something like this can happen in humans too.
How many genes are there in the Y chromosome?
Women have two X chromosomes while men have both an X and a Y chromosome. Although the Y chromosome is much smaller, containing about 55 genes compared to the X chromosome’s 900, it plays a vital role in determining male sex by promoting the development of testes in the fetus.
About 12 weeks after conception, a master gene on the Y chromosome, known as SRY (Sex Determining Region Y), sets in motion a genetic pathway that leads to the formation of male reproductive organs. This gene also works by stimulating another key gene, SOX9, which in turn leads to the fetus being born a boy.
… then after so many years the male chromosome will disappear from the earth
Most mammals have a similar X and Y chromosome structure, but this system is fraught with challenges due to unequal gene distribution between males and females. Interestingly, the Australian Platypus has completely different sex chromosomes, just like birds, suggesting that mammalian X and Y chromosomes were once normal chromosomes.
While the number of Y chromosomes was 900 166 million years ago, now it has reduced to only 55. If this trend continues, then according to this, the Y chromosome may disappear completely in the next 11 million years.
New hope but big concerns too
The development of a new male chromosome after the disappearance of the male chromosome in mice may be a good news for humans, but scientists also have some concerns about it.
Genetics expert Professor Janie Graves says, ‘There are some dangers associated with the development of new sex-determining genes. Different types of male sex genes may develop in different parts of the world. This development may also lead to the development of a new type of human race.’
Source (PTI) (NDTV) (HINDUSTANTIMES)