A COMPANY called 23andme.com launched last week and got wads of media attention for being the first user-friendly website devoted to home genomics tests and analysis. For just $1,000, the company will take a swab of your cheek, sequence your genome and tell you a bunch of things about how you fit into the Family of Humanity. The company will also allegedly give you nifty details about yourself, such as whether you have athletic abilities or a propensity for disease.

And 23andme is just the beginning. Another company called DeCode offers a similar service called DeCodeMe, and more are sure to follow. People are desperate to understand themselves, and so they turn to genetics as if it were a self-help manual instead of a still poorly understood science.

While there are many theories about how genetic expression works on our personalities and health, there are few solid facts. Some tests, such as those for various kinds of developmental disabilities, have provable results. But many genetic tests, like those 23andme claims can reveal "athletic ability," are the biotech version of snake oil.

The question I keep asking about home genomics kits is whether they're any worse than, say, the self-help industry. Both promise to fix people by making vague pronouncements based on a little science mixed with a lot of rank speculation. Both do help people figure themselves out some of the time. And both are often quite costly—therapy can go for hundreds of dollars an hour and so can self-help classes.

I'm wondering, essentially, if there's something exploitative about the services sold by 23andme. Probably not—or no more so than the chocolate sold by Godiva, which is also shockingly expensive and basically useless. If people want to pony up the cash to have a little fun, why not? But I don't think it is just a little fun, like chocolate or "find the inner you" classes.

What I see when I look at a site like 23andme is nothing less than the future of eugenics. I don't mean the scary capital-E eugenics of the 1930s that involved killing Jews and sterilizing "loose women." I mean wild-type eugenics, the kind of genetic engineering that happens in nature without any intervention from dictators. It's the sort of eugenics that results when people of the same races and classes tend to marry each other. It's the genetic engineering that results when men can choose their mates but women can't.

23andme and websites of its ilk are just one step away from being social networks based on genetics, sort of like Facebook for people who want to compare genes instead of beer bongs. Currently that's not what 23andme is trying to be, though it does offer users the chance to compare their genomes with those of the general population. But you can bet that once these companies start amassing tons of genetic data, they're going to want to do something with it. After they sell it to insurance companies—who will use it to charge higher rates to people with "bad" genes—they'll sell it back to users in the form of social networks. Or the users themselves will post their data for all to see, the way they already cluelessly post pictures of themselves passed out naked on MySpace.

And out of that data will arise the first dating service based on genome compatibility. What is genome compatibility but eugenics? While newspaper stories about the new personalized genomics services trumpet the arrival of the future, I see nothing but the past. This isn't science for the masses; it's not enlightenment. It's just the same old crap, dressed up the in language of modern biology and tricked out with a zoomy Javascript interface. And I do think it's worse than self-help, which is sometimes good for you. It's worse than Godiva chocolate, which is at least tasty.

Home genome kits, at this point in time, are likely to confuse people at best and confirm their prejudices at worst. I'm not saying people shouldn't buy these kits, or that they won't be useful someday when we actually understand our genomes better. I'm just saying we shouldn't use them to understand our places in society. Certainly we shouldn't use them to find genetically compatible friends. But I'm pretty sure we will.

Annalee Newitz is a surly media nerd who thinks your genome isn't worthy of hers.

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