Y-less days ahead

Two features literally stand out in male anatomy. Aside from the obvious southern feature whose companion adjectives are often stretched way out of proportion by Adams themselves, there is the Adam’s apple up north. I do not understand why after that major fallout in the Garden of Eden, why it is Adam who got to keep the fruit by naming a body part after it and Eve simply got to keep the sin and the blame. Adam has always insisted he was there first despite scientific evidence to the contrary (yes, the science story is that "Adam" is the "second sex" because for the first billion or so years, single cells managed by themselves until by some mutation, the Y chromosome, as a variation, was born). But okay, Adam, even if I suspend my science for a while and say you were there first, it would mean you were already very familiar with the terrain of earthly paradise and had the original list of do’s and don’ts of garden rules. But how did you deal with curious Eve when she arrived? You got excited by her curiosity and went along with it. So at the very least, shouldn’t Eve keep the souvenir which has earned her and all the other Eves a reputation? And why "apple" when it looks like a piece of lanzones that came down the wrong pipe and got stuck there? Ys are always trying on exaggerated metaphors for size. And if you think I am too picky with my fruits, look what a new book on male genetics revealed: All of Adam, not just his apples, northern or southern, seems to be falling from grace which means the Y-ness that their chest-thumping bearers so gloriously declare is now turning out to be no less than the very thing genetically escorting them out of evolution. The Y burse is turning out to be Adam’s curse.

A "curse"? Yes, because the same things which make a Y chromosome as the self-declared power that it is are also the reasons why geneticist Bryan Sykes in his new book, Adam’s Curse. A Future Without Men (London and New York: W.W. Norton, 2004) thinks the Y is on its way out. I am sharing here the science of a Y himself, a bearer of Adam’s genetic curse who, being a scientist, had to reveal some crushing facts about why he thinks the Y will be extinct in about 125,000 years. He cited sperm count trends covering five decades that undoubtedly revealed a shrinkage in Adam’s basket (and I can imagine, his hubris.) From 1940 to 1950, over 50 percent of men had a sperm count of over 100 million/milliliter but it has continually gone down over the decades to only 20 percent of men in 1980-1990, and while over 15 percent of men in 1940-1950 had less than 20 million/milliliter, it was up to 25 percent in 1980-1990. In short, the ones who have less are more and the ones who have a lot are much less now. And with this muting of male fireworks, he proceeded to nail the coffin of the Y chromosome to extinction several more ways.

Sykes cited the fact that there are more active genes in the 16,500 bases of mitochondrial DNA (the ones passed on from mothers to daughters) than in the 60 million bases in the Y chromosome. Steve Jones, my favorite geneticist-author of Y The Descent of Men (NY: Houghton Mifflin, 2003), called these junk, inactive bases "corpses" that make up the majority membership in the Y artillery unit. Dead guys cannot join the parade with the rest of the active bases that code for proteins responsible for all our functions and make-up.

Next nail, only when a Y-bearing sperm reaches the egg first is the sex of the baby turned from its default X mode. The genetic default is X since the egg bears only X chromosomes and half the sperm cells bear X chromosomes. It is the Y-bearing sperm cell which shifts the default X mode of nature. As such, it cannot recombine with the X (unlike with females who have XX and thus, can repair each other) and this is a problem in the gene level because genes need to recombine to repair themselves from errors in mutation and prevent decay. The Y does a lot of mutations (1,000x before popped on to a sperm) to keep up with life-long sperm production compared with the fixed amount of egg production (which divides 24 times before egg is released for fertilization). But the problem with Y-sperms does not stop there, Sykes said, since a big percentage of these are not even shaped right to swim in the direction of the egg. At first, scientists thought that maybe a big portion of Y-sperms of primates are really shaped to get lost finding the egg but when they checked the Y-sperms of our closest kin, the chimps, they saw that they were perfectly shaped to get to their destinations. Apparently, the refusal to ask for directions is really a peculiar human Y trait.

So in the absence of a chromosome to recombine and repair itself with, what does a Y chromosome do, specifically the SRY (the Sex Determining Region of the Y at the tip of the Y chromosome)? Well, blush if you must but it does the only option open to it – it "talks" to itself, i.e., it just recombines with itself, which Sykes said shuts off the chances for new genes to arise and therefore renders it increasingly unfit to cope with the ever-changing conditions of the environment. That is a pretty sharp nail to the genetic Y coffin.

The last nail Sykes hammered on to the fate of the Y is the fact of its location. Y chromosomes find their home in the testical cells of men and suffice it to say as Sykes did that, "the testis is a very uncomfortable place for a chromosome to be" because it is that part that "warms up" since it is sat on and covered in clothing required for jobs that require long hours of driving, operation of heavy machinery and other industrial jobs. Studies he cited showed that the fertility of these men has been adversely affected by these kinds of jobs.

In sum, the Ys are a billion years "late" in the party of evolutionary life and when they do join the journey, they keep getting lost, refusing to ask for directions and insisting they have the more detailed life map when it is the XX who has it. And by the time science is able to make sense of the Y presence or confusion, the Ys now seem to be on their way out. If at all readers feel sorry for Ys, think of the XXs. Think of the XXs who necessarily have to take big leaps of faith to love Ys in varying flavors but who are all either late, lost or on their way out. But what do we do when the closest genetic kin are chimps? (And to be on the safe side, I got a book called "How To Tell Your Friends from Apes" by Will Cuppy.)

Right after I made my notes for this column while sitting in a café, I heard the theme music from "Superman" coming out of a man’s mobile phone nearby. Hmm, Superman, eh. That’s what he thinks. If Sykes is right, the future will not be super for men. In fact, if Sykes is right, there is no future for men. The news would break his heart.

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