Thursday, April 16, 2009

CBX2: The Age of Chromosomes is Over!

By Sophia Siedlberg

The New Scientist (1) published an article about a seven year old girl who was "diagnosed" as having XY chromosomes, but has a uterus, ovaries etc. As usual the popular press described what the team in Zurich had found, led by Dr Anna Biason-Lauber as a girl who had violated the rules of "maleness" and she therefore "provided a key to understanding how maleness works". There is however a bit of a bombshell for all those Chromosexuals out there who get sexual satisfaction in condemning such a child as "a genetic male". Dr Anna Biason-Lauber has discovered a more important truth here. Sex is not down to chromosomes!

CBX2 on (wait for it) Chromosome 17 acts like the real "Male master switch" and most XX females will have a working copy. So does that makes them genetically male then?

There are two key points to remember here, firstly the MSRs on the Y chromosome are not the "male master switch" (In plain English SRY is not the six pack penis gene it was said to be) and secondly the fact that the "real master switch" resides in Chromosome 17 and everyone, male or female has a copy of it.

Anyone with half a brain may start to realize that sex differentiation is more complex and in terms of chromosomes, more diffuse than the commonly held misconception of everything being on the 23rd pair of chromosomes. What Dr Anna Biason-Lauber has found is simply the fact that sex differentiation is not what people have for years thought it to be.

Look at this both ways (as most people were taught to believe the SRY on the Y chromosome is the root of all maleness): before SRY there is another "master switch" that if present and if expressing "allows" SRY to express. So SRY is clearly not the root of all maleness. Add to this the simple fact that CBX2 is found on every man and woman's genome, and resides on chromosome 17 not X or Y. Suddenly male and female are not quite so distinct. After SRY we again find a situation where all the relevant genes have to be there, have to express in a given way and they can also be found on either the X or the remaining autosomes. Rendering the “oh so sacred” Y chromosome as something that will increase the probability of a male birth but little more than that.

What CBX2 shows is that people cannot use genetics as an excuse to say to XY women, "They should be men". For ten years or so genes expressing after SRY have been shown to be as important when it comes to making someone "genetically male" or "genetically female" (If fools want to be so arbitrary about it) but now it has been found that SRY depends on a gene in the autosomes to express before SRY can. And if it doesn't, SRY or no SRY, the end result is a female.

There is no excuse now for anyone to think that XX = "Girl" and XY = "Boy". It clearly does not work that way. You are only "genetically male or female" if you have all the genes line up to produce an unambiguous phenotype of one or the other sex. Since this is also not so clear cut, even talking of "Genetic sex" is foolish, and to claim a woman or girl such as the one mentioned in the New Scientist is "genetically male" is little more than petty minded ignorance.

The next time someone says to me, "Such and such is genetically male because of their chromosomes", I will simply maintain that in order to draw such a conclusion, they are deliberately ignoring how DNA really works and as such must be "genetically pig ignorant".

The age of chromosomes is now over. Like it or not, chromosomes are not the final markers of sex and never will be.

The very second Dr Anna Biason-Lauber published her findings was the very second the imagined absolute nature of chromosomes came to an end. If people are going to describe sex in terms of genetics, they can only say it truthfully now: Chromosomes simply hint at the presence of a set of genes (Polygenic array, ah vindicated!) that would lead to a particular outcome, but nothing more.

Being male or female is not a question of genetic checklists involving chromosomes. Being male or female is an adapted state of being as I have always said, and this proves it. Genetically sex is a complex set of variations, more complex than "social constructs and some mythical gender spectrum." The real spectrum is the entire human genome and that differs from individual to individual. Someone’s approximation to a given sex is like their fingerprint, unique to them. And when people realise the full consequence of that, the two sex system and not just the "gender binary" face a very profound challenge.

Has society got the balls (or ovaries) to grasp that? Or will society still insist on saying something dumb like "XX for a girl; XY for a boy"? Only time will tell, but since Dr. Anna Biason-Lauber published that paper, the age of chromosomes should be consigned to the dustbin of history along with other mistakes like eugenics.


(1) Journal reference: American Journal of Human Genetics (DOI: 10.1016/j.ajhg.2009.03.016). Issue 2704 of New Scientist magazine, page 14.

This is a service of the Organisation Intersex International

1 comment:

  1. You're right, abnormal genetic mutations should always be used to qualify normal biological function.