09 October 2009

Flu Attacks

Both my kids have had the flu and they are now almost recovered. One of my colleagues and one of her daughters also have the flu. This is notable this year because flu fear is high since H1N1 (aka swine flu), which first surfaced last year, has killed the kind of people for whom flu is normally just an inconvenience. For example, a healthy 25 year old who died from flu in Colorado this month. Absences are high at the local elementary school, and the recreation center's cross country team has had notable numbers of participants out every week due to flu.

I've had a season flu shot, but not an H1N1 shot, and I'm crossing my fingers. I suspect that I will soon learn if I'm feeling less than wonderful due to flu, or just from lost sleep from everyone else being sick and waking up in the middle of the night.

It isn't terribly reassuring that I also learned from an article in virology yesterday evening that one of the main ecological purposes of viruses is to kill things so that they biomass can re-enter the food chain. Viruses kill 20% of the plankton in the ocean every single day (which, fortunately, grow right back). The white cliffs of Dover? A grave yard of diatoms killed by viruses.

Of course, that isn't their only purpose. Viruses are also "gene brokers." They are probably responsible for the fact that there is a slug which can perform photosynthesis with the cooperation of algae organelle that it harvests by eating them. Indeed, most plants and animals have DNA that can probably be traced to viruses.

Viral Genetic Change

The power of viruses in action in their gene broker role is humbling. For example, scientists gave male monkeys in a species where male monkeys are always red-green color blind a virus that carried a gene for red-green color sight. Suddenly, and for the rest of their lives, they could see red and green. In the middle of their lives, a virus permanently changed their genes. You usually think of as one of the quintessential and immutable parts of the definitions of "you." But, this isn't always the case. Humans genes are sometimes changed by viruses as well. At least one such virus has been documented in modern Latin America.

How Far Should Gene Therapy Go?

So far, gene therapy via intentional infections with custom designed viruses is still in the experimental stage. Fewer than a couple dozen people, all in the 21st century, have been treated using it. But, the principle has been established. Sooner or later, it will become one more prevention and treatment modality along with medical treatments like antibiotics, vaccination, surgery, physical therapy, vitamins, radiation treatments, anti-viral drugs, and chemotherapy.

Author Kate Elliott's Jaran series took this theory to a logical extreme where the entire civilized human race intentionally altered its genome with gene therapy to give itself incredible longevity, fixing a host of disease causing genetic flaws.

Are we smart enough to decide what to change? It is hard to fault science for dramatically reducing (and in some cases virtually eliminating) small pox, polio, diphtheria, measles, mumps, rubella, and more by engineering our immune systems.

Would it be so bad to make available genes closely associated with longevity found in the existing population? Haemophilia (a blood clotting disorder) is the first well understood genetic disorder; it is genetically simple and well understood. Would a gene therapy to treat haemophilia be a bad thing? More frivolously, what would be so bad about giving healthy people, who wanted it and gave their informed consent, a gene that allowed them to see ultra-violet colors (a trait found in butterflies, most birds, some fish and possibly even very rare human beings)?

I think it is fair to say that our society no longer sees modifications designed to improve physical health as a sacred frontier that should not be crossed. There are utilitarian concerns about unintended consequence and side effects, similar to those involved in prescription drugs, but not deep moral concerns.

Mental health is another issue. Lots of mental health conditions have a strong genetic component.

Some of these appear to be far too complex to treat with gene therapy, because they seem to involve the cumulative effect of many small genetic issues, rather than a small number of particular genes (bipolar disorder and schizophrenia are examples). But, surely, other genetic mental health conditions are far more straight forward.

Some anxiety conditions are symptomatic almost from birth, and fairly simple genetic models may explain many anxiety disorders. Blood testing for panic disorders may be around the corner. The U.S. Army has been doing blood testing on new recruits for vulnerability to stress related disorders for about three years now. About 40% of people with agoraphobia (often crudely described as a fear of crowd), for example, have a relative with agoraphobia, which has been linked to a chromosome 3 trait. Many panic disorders and obsessive-compulsive disorder may likewise have relatively straight forward genetic origins. If a safe, effective gene therapy for agoraphobia were developed, how many agoraphobics would happily allow the gene that causes this condition to be altered in a way that would permanently end this condition?

Under what conditions is it worth tinkering with our genomes to mitigate these traits, which may have historically had adaptive value but may be maladaptive now? Anxiety disorders are currently one of the most common mental health issues. Would it matter if some subset of the population chose to forgo gene therapy for anxiety disorders with simple genetic models, keeping those traits in the gene pool, but at lower frequency rates? At what point does anxiety become a personality trait rather than a disorder? And, it is right to use gene therapy to change one's personality as opposed to curing a disorder?

Are we brave (or foolish, as the case may be) enough to address these traits permanently through gene therapy, much as we do temporarily through drug therapy? Are the risks of declining neurodiversity too hard to evaluate relative to the risk of declining physical diversity associated with genes that have less of a mental health impact?

Are there mental traits, IQ perhaps, that are simply better in almost all cases? Who decides? Is a brain-body distinction even something that makes sense?

There is already a history, which is decidedly mixed, of people intentionally altering gender and hormonal identity through castration and more recently chemical castration. This has been done to preserve male soprano voices, to create trustworthy eunuch servants, to tame violent sexual predators, and the purify holy men. What if this was done with gene therapy instead?

Suppose that a ten year old clearly had a transgender identity? Would it be inappropriate to use gene therapy to change that child's genetic gender before puberty through gene therapy to match that child's self-identity?

These decisions are no longer in the distant science fiction future. If my generation does not face them, my children's generations probably will.

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