grasshopper

A few months ago I found out for scientific certain that I've only 45 chromosomes. How I have managed to sit on this fascinating fact without blogging about it will forever remain a mystery. Whatever, I'm blogging about it now.

Casting my mind back to high school biology, I'm pretty certain that we were taught that humans have 46 chromosomes. FACT. I recall pointing out that my sister has 47, and as per usual my teacher looked at me with utter disdain and then told me to shut up. So I liked to challenge some of the things he taught us. Especially the stuff I knew to be dubious or just plain wrong. Oh, I was such a trouble maker.

Back then I knew that people with Down Syndrome had 47 chromosomes. I think I read it somewhere. Probably in the library. I used to ride my bike there some weekday afternoons and on Saturday mornings, after having spent every lunch break possible in the one at school. And while I was told by my mother that Down Syndrome seemed to run in the family, it never really bothered me to find out what that meant, exactly. Oddly, I just always assumed I was a 'carrier' and it wasn't until recently that I realised that that assumption was a possibly dumb one to make.

Turns out it wasn't that dumb of an assumption. Not really. It turns out the chances of me being a balanced carrier were 50%.

Heads or tails.

They are not particularly good odds.

Of course I am a balanced carrier. And perhaps I deserved to be, after using it as an excuse to ward of rude questions from almost strangers about the curious absence of children in the early years of my first marriage. Why is it that people seem to think it's OK to ask such a personal question? Is it a throw back to a (horrifying) time when women couldn't really manage their fertility with any sort of guarantee, and folks believed the hype about marriage being for kids? At any rate, it was easier to tell them that I had 'problems', rather than try to explain to the idiot masses that I'd married for love and love only. Occasionally I would go so far as to explain that I didn't want children, but that caused strange reactions in people. Especially in those who had children. After a while I learnt that people didn't want to hear the truth, as it challenged their preconceived ideas too much. It eventually got to the stage where I would just say 'No', with no explanation. Let them work out how rude their question was.

When I decided to find out about my carrier status for sure, I actually allowed myself to become slightly optimistic that I wouldn't be. That I would be normal and that I would have one less thing to worry about in my life. Though I never said any such thing out loud, keeping an exterior of cool and calm indifference. Because that's me, you know. Cool. Calm. Indifferent.

Balls.

To be completely honest, I'm a strange mix of disappointed, resigned and...happy? What's another word for happy? Happy isn't really what I mean. Maybe chipper is a better word. I'm chipper because it turns out I am exactly the same as my eldest sister, also a balanced (14-21) Robertsonian Translocation-ist (not a real word). And my sister is ace.

As a rule, the normal human chromosome set up is of 23 matched pairs, making 46. The chromosomes are inside the nucleus of almost all the cells in the human body. I say almost, as they are not found inside our (released) red blood cells (the red blood cells do have them while they are being created inside our bone marrow, but not once they are released). And in the sperm and egg cells, there is normally 23 chromosomes, which when a man and a woman love each other very much, and they express this love by the man putting his pe...

I'm sure you get the picture.



In the diagram above we have a bunch of normal chromosomes. Notice the last two pairs are either/or, so as to receive the esteemed status of 'normal'. There are sex chromosome abnormalities, but we aint talking about that here today.



And here is a hastily prepared diagram of my chromosome make up. Specifically one of my 21 chromosomes wandered off and attached itself to a number 14 chromosome, presenting itself as one chromosome with two bits of genetic information. This is how I manage to appear normal and lead a normal life, because all my genetic information is present and accounted for. It's just arranged differently.

This was all predestined. Nothing happened in utero or post birth to make me this way. The genetic material in the egg that was half of me would have looked like this.



This was an egg that was inside my mothers body at birth. I am not sure at what stage during foetal growth that we grow our eggs as female humans, but I do know that we are born with our eggs and that the genetic make-up of those eggs is already decided. Those eggs already have 23 chromosomes inside their nuclei. Or in the case of me, my eldest sister and by deduction, my mother, 22 chromosomes. Because 21 is actually 'attached' to 14.



Above is a diagram of the chromosomal information that was inside the sperm that fertilised the egg that was me. My mothers egg contributed a X chromosome, and my dad contributed an X, making me a girl. And my dad contributed one 14 chromosome and one 21 chromosome. And because the number 14 chromosome that my mum contributed contained the genetic information of a 14 and a 21, we got me.

You get meh?

Now, armed with all this information, you might start to think about those other eggs. The ones that contain the chromosome 14 that does not have the chromosome 21 attached to it, and that did not get a copy of the other number 21 chromosome. What happens if one of those eggs is fertilised? Because each month, a healthy average woman releases just one egg (the ovaries take it in turns, alternating). Well, that pregnancy will absolutely probably highly likely terminate itself early doors.

So here we have potential miscarriage chance number 1.

Then we look at what might happen if an egg that contains the chromosome 14 that is carrying the genetic information of 21 on it and also a copy of the chromosome 21 is fertilised by a healthy normal sperm. The human body is so clever that it might look at this stuff early doors and try and fix it. No shit. It will try and recover the situation by deleting some of the information. Problem is, it most likely wont get it right, and something happens that I don't quite understand, but the upshot is that we have potential miscarriage chance number 2.

And it goes on, and out of the six possible outcomes for a pregnancy for me, the Suburbanhen, three of them are not viable, two of them are and one of them, if carried to term, results in Down Syndrome. I put that 'if' in, because it turns out that there is a high rate of natural miscarriage amongst Down Syndrome pregnancy's as well.

You know what? I absolutely love knowing all this. Except that it's kind of like knowing your partner is cheating on your monogamous relationship. It's only fair that you know, but with the information comes choices. If you didn't know, you wouldn't have to decide whether you should forgive them.
With all this knowledge, I am faced with a whole bunch of choices and frankly, I am not the best decision maker. Historically I have made some ridiculous decisions, some of them so ridiculous it's unfathomable. This is the bit that is sending me INSANE.

Earlier in this piece I made reference to how I used to tell people I did not want to have children. On any given Tuesday this could still remain true. I have lots of practiced reasons why I do not want to have children. Yet in the same breath, this year something changed and now I do. Faced with this complicated set of emotions, I wanted to find out if there was anything else that would make the decision harder, hence finding out all that shit about my chromosomes. And of course, there is to be much, much more to any decisions that we make about springing forth any Bargain-Hen babies. Not to mention in the very least how poor old (he's SO old now) LB feels about any of this. Because let's be honest, he married a woman who emphatically did not want to have children, and he only did that last year. LAST YEAR! Could you possibly imagine how he must be feeling about all of this? I can, and when I think about it too much I find myself drawn to researching how much it would cost to get me and my cats back to Australia, where I can safely stop ruining his life. And the only thing that has stopped me from leaving is LB himself, who for some reason or another has gotten over any animosity he might of felt and has decided that the cats and me should stay, turncoat ovaries and all. In fact, he seems to want to take some sort of responsibility for it.

Are you insane yet? I wrote this post in the hope that it would cause a whole bunch of people to go insane, so I wouldn't be alone in it any more.