For Now, We Men Are Safe!!
- February 24, 2012
- Posted by: INSIGHTS
- Category: Inside India
Misandrists were thrilled when they heard two researchers say that men were on the verge of extinction – in 2003, Brian Sykes, a genetics professor, in his book Adam’s Curse:A Future Without Men, predicted that men would vanish from earth within 100,000 years as their Y chromosome was slowly decaying genetically. Again in 2009, Professor Jennifer Graves of Australian National University suggested the same, but as a consolation she predicted it would take another 5 million years for men to say goodbye to earth and women.
What has Y chromosome anything to do with extinction of men?
Humans carry 23 pairs of chromosomes in each of their cells. Of these one pair is called as sex chromosomes – women carry two X chromosomes, whereas men carry one X and one Y chromosome. These chromosomes carry DNA, or the blueprint of our entire character, well packed to carry this blueprint firmly from one generation to another. In other words, these chromosomes carry genes that define us.
Y chromosome is special, not because it is carried by men, but because it has changed itself over millions of years from being X chromosome once upon a time to Y chromosome now. Yes, research has proved that 166 million years ago both chromosomes were similar.
Y chromosome carries a crucial gene called SRY (sex determining region on Y) gene, which is necessary for the development of testis and production of male hormones during embryonic development.
Apart from this gene, Y chromosome also carries other genes that help make man what he is.
Now coming to extinction of men theory, it was thought so because when both X and Y chromosomes were sequenced, it was found that Y chromosome carried few genes compared to X. To be precise Y chromosome carries 45 genes, whereas X chromosome carries 1438 genes!! (this might explain why women are difficult to understand – I remember Stephen Hawking the man who unraveled mystery of our universe, saying that he found it difficult to decipher a woman’s behaviour!)
Now a question will arise – why Y chromosome is losing its genes? If you see the picture of X and Y chromosome together (see below), you will realize how this poor creature, Y chromosome has lost its weight over the years!
So, why has it lost its genes then?
Answer lies in genetic recombination and mutation. It is a process whereby chromosomes mutually exchange genes and evolve. For example, both X chromosomes present in females, recombine each other to make females evolve better, they make genes stronger and healthier.
But, when Y chromosome was evolving, giving rise to genes that would define men, this recombination started affecting X chromosome, because it did not need any genes from Y chromosome. So, Y chromosome started concentrating its all genes in the region around SRY gene, only those genes that were necessary were packed there so as to keep away from X chromosome genes. Meantime, the other region of Y chromosome started shrinking as it did not have any more genes to carry. (see picture)
There is another reason – high mutation in Y chromosome. As it is placed in high oxidative condition of testes, and as it undergoes multiple cell divisions during production of sperms, it is vulnerable to high mutation. Mutation is change in gene structure or sequence. As there is little exchange between X and Y chromosomes, mutations and deletions over many million years have made Y chromosome look like Lilliput compared to X chromosome. Remember, these Y chromosome is faithfully transferred as it is from father to son without much change. If father’s Y has mutation, that is passed on to son, and if son gets mutation on his Y, he will pass it on to his son.
So, the male extinction theory basically says that as Y chromosome will die, so will all the men. Without Y chromosome there are no men.
But, yesterday, BBC reported that, men need not worry, as another research has proved that it is not all true that Y chromosome is dying fast.
Another Jennifer has come to the rescue of ‘man’ Kind – Jennifer Hughes of Whitehead Institute in Cambridge, Massachusetts.
She compared human Y chromosome with that of chimpanzee and rhesus monkey and found that, genetic decay in human Y chromosome is minimal in recent years, and human Y chromosome has lost only one gene in last 25 million years! Presently there is no sign of any decay in the Y chromosome.
That’s a good news! for men, at least for few million years more.
And for misandrists, they will have to keep hating men for ages to come. Sad though.
But, here is a lesson for men. We are not superior. And nature has its own ways to mend our ways. We, better behave as equals, if not inferior (Y is small). I wonder, how come men dominated women with this little Y all the while!! Move on to sociology from genetics now.