Why we can't say bye to Y

Men surprised me this week. No ladies, I did not go soak in some tribe where I found men who looked like those men in the movie “300” but were sensitive, did housework and detested blowing up things. I am still in the city and I was busy reading up on the latest science findings on their body parts. And surprisingly, the biggest achievement of men turned up in their tiniest parts — in their champion chromosome: the Y. Recently, scientists have unraveled that the Y chromosome has been able to evolve more rapidly than any other genes in the other chromosomes. The Y chromosome which human males bear, is not going to wither and die out as predicted. So hold the despedida, for now.

Since the human Y chromosome has been sequenced seven years ago, it has been thought that this puny chromosome, the tiniest of all the chromosomes, will soon disappear. Each of us, in each of our cells (except the red blood cells and sperm and egg) carries 23 pairs of chromosomes — one from your mom and one from your dad. If you are female, then you generally have a pair of Xs for your 23rd pair, but if you are male, then you generally have X and Y. Generally because there are conditions where you can have outer female body parts but have X and Y chromosomes. There are also rare genetic cases where you have XXY or XYY.

Let us put it this way, if you can think of yourself as a long film, think of being made up of 23 CDs worth. Your genes are the many episodes in each CD. Each CD comes in pairs so that in case there is something wrong with one CD, you still have the other. In females with XX as the 23rd chromosome, the corrections could easily be done. But for the Y chromosome which is paired with an X, it has no one like it to come to its rescue when there is a mistake in the Y. There is no other Y next to it to give it the episodes it needs. This is what led geneticists to believe for a long time that this cannot go on indefinitely because too many errors could just cause the Y itself to obliterate its Y-ness. And since the Y chromosome is what makes a baby, male, a fading Y spells an eventual farewell to men.

But comes this redeeming scientific work on the Y was led by David Page and Jennifer Hughes. What it did was compare the genes in the human Y and that of the chimp. The scientists chose chimps because they are our closest genetic cousins as we only differ in less than two percent of our genes. This being so, Page and his colleagues compared the Y chromosome which they had sequenced last 2003 with the sequencing of the chimp Y which they just finished. They expected it to be very similar so they were very surprised to see how different it is. This means that the human Y has managed to evolve even faster than the rest of the genes in humans. Their work is published in the journal Nature last Jan. 13 and is entitled “Chimpanzee and human Y chromosomes are remarkably divergent in structure and gene content.”

In case you are wondering what the human Y chromosome was pretty good at in terms of reinventing itself even without the help of another Y chromosome, please know that it is in the area of sperm production. I guess if you were a Y chromosome, it would really make sense to work on your parts whose failure could spell your doom. The scientists have yet to figure out how the Y has managed to reinvent itself to stay alive when it did not have help from another Y chromosome.

The scientists were quick to note in their press releases that this does not mean that men are more evolved than women. This just means that the chromosomal champion of men, the Y, has managed to institute measures to keep itself from dying. But I am sure, we would hear from men who upon hearing this, would think it a personal accomplishment of theirs and do the usual bravado of chest-thumping. They would declare that their gender has shed the ways of chimps in far-reaching ways than the female. And we ladies would sit you down, hold you ever so sweetly, and while looking deeply in your eyes, confess: “You could have fooled us.”

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