Friday, April 3, 2009

Lesch-Nyhan thoughts

Yesterday I went in the Bookstore. I was checking out this non-fiction book I don't know the name of, by the guy who wrote The Hot Zone. The last chapter was on something called the self-cannibals. So I read it, always being intrigued by anything that sounds that strange.

These self-cannibals are victims of a hereditary disease called Lesch-Nyhan disease. It's a sex-linked disease, which means it's carried on the X chromosome, much like hemophilia. Women don't get it, because they typically have another X chromosome to take over from the defective one; men do get it, because they only have one X (and one Y, remember?). They don't have a functional copy to erase the effects of the defunct X.

This disease intrigues me very much. You can tell if a child has it because right off they will urinate orange sand. Yes--urinate orange sand. It's from a buildup of uric acid in their blood. Lesch-Nyhan is basically the suppression of a particular enzyme that keeps uric acid levels manageable. Because of this, up until recently Lesch-Nyhan people would die of gout and kidney failure by typically the age of four. Now, most Lesch-Nyhans die around age 20, though some live much longer.

But the amazing thing about this disease is that the physical aspects of the problem are hardly the most devastating. And not only that--this other aspect of the disease has apparently no genetic marker. And sufferers of Lesch-Nyhan have the same exact brain structure as typical, non-Lesch-Nyhan people.

Lesch-Nyhan people are self-inflictors. Self-saboteurs. They compulsively destroy their own lives--even as they cry out for help. A picture in the book I was reading showed a boy who had chewed off both of his lips, and his own hands had torn out his palate bones one by one. These people bite off their own fingers, even as they scream for restraints. They beg for people to tie their hands to chairs. One man I read about used a fork to hack off his own nose--in a restaurant. As he screamed for people to stop him.

And this behavior is not limited to physical self-sabotage. These people are the cruelest to people they love most. You can tell a Lesch-Nyhan person loves you because they will never say a kind word to you. You can tell a Lesch-Nyhan person hates you because they will be extra sweet to you. If you ask a Lesch-Nyhan person what they want to do, they will tell you the exact opposite of what they actually want.

This is called a behavioral phenotype. It is amazing to me because I cannot fathom a disease that could sidetrack the most basic of human instincts: self-interest. I am incredulous at the concept of a disease that would cause a person's body to harm itself. And even more, I am amazed at the concept of a disease that would make a person compulsively lie to prevent his own happiness.

This particular disease is troubling to me. I wouldn't say my faith is shaken, but I had never contemplated the idea of a behavioral phenotype--a set of behaviors genetically predetermined that simply cannot be sidetracked. The mere existence of this sort of disorder is a strong argument for the third tenet of Darwinism, the one that repulses me to the core. The one stating that people cannot make choices, because our genetics predetermine everything about us. The one claiming that people are no better than animals, destined to evolve in the same way. The one that says that free agency is a mere delusion.

Because if there is such thing as a behavioral phenotype, who is to say that anyone truly has free agency?

If everyone's behavior is determined by his or her genetics, then there really cannot be responsibility. I remember this one time in an elevator, my own genetically-mutated brother reached out and grabbed some random girl's boob. Awkward. We tried to pry his hand off her boob (awkward!!!), and when it was over, no one thought worse of my brother, not even that girl whose boob it was, because we all recognized that James has no real control over his own behavior. You can't hold someone accountable for something they didn't choose.

Do you see what the issue is here?

I just have to wonder, how many of my obsessions are manifestations of my own behavioral phenotype? Arguably, all my actions are. Arguably, every choice anyone makes is really only a manifestation of predetermined genetic makeup.

And yet, if this is true, then what is the meaning of life?

Weird.

So anyway, I guess I'll come back to this post later. Anyone else find themselves bizarrely affected by the knowledge of this disease's existence?

1 comment:

Vanessa Swenson said...

I see you posted at 3:54am. That was right after I went to bed.

You know, I think about this type of problem sometimes--not the Lesch-Nyhan disease which I'm going to try to forget. But the whole genetic vs. agency vs. choice thing. One time a professor of mine was talking about his dad who drank himself to death in his 30s. My prof said that he might have the genetic disposition to alcoholism, but that there was no way he was going to drink to find out.
I know that there are some diseases and situations that are beyond this scope, but I think all to often genetics is used as an excuse to not try to get better or whatever.

I wonder what my compulsions are...