Really good op-ed today by Dr. Robin Cook restating the argument that genetic profiling will mandate single-payer health insurance.  Essentially, we're finding that most all serious diseases have some sort of genetic component.  That doesn't mean they're predetermined (indeed, genes interact with environmental and lifestyle factors to what's turned out to be a really surprising degree), but it does mean we're beginning to create technology able to identify an individuals risk factors for a whole host of conditions, essentially handing them a list of all the terrible ways their body may rebel against them in the years to come.  The upside of that is, as I alluded to before, many of our genetic predilections can be sidestepped by lifestyle.  If we know we're at risk for disease X, we will know to lead lives that short circuit disease X.  Oh, and there's another upside: genetic profiling is going to make private insurance absolutely impossible:

Not only is microarray technology easily accessible, but for-profit private insurance companies have strong incentives to use it to protect their bottom lines by denying service, claims or even coverage.

It is precisely this danger, however, that may lead to a great breakthrough: the inevitable movement to universal health care. In this dawning era of genomic medicine, the result may be that the concept of private health insurance, which is based on actuarially pooling risk within specified, fragmented groups, will become obsolete since risk cannot be pooled if it can be determined for individual policyholders. Genetically determined predilection for disease will become the modern equivalent of the "pre-existing condition" that private insurers have stringently avoided.

Once individuals can find out their likely genetic destinies, the whole concept of private insurance goes up in smoke.  The incentives for hyper-accurate cherry-picking are simply too great and te disincentives to finding our genetic risks too large.  Indeed, if only patients are allowed to see their genetic profile, they'll know exactly which insurance to choose.  The healthy can pick the most minimal of plans while those with an atom bomb of a microarray (the slide used to read your genes) can sign up for the most kickass, comprehensive plan available.  That destroys the ability of insurance companies to turn a profit.

Conversely, if we let the insurers see our microarrays, no one will ever get them done.  We don't need to go too deep into a Rawlsian veil of ignorance to realize that a bad readout would make health insurance prohibitively expensive just when we know we need it most.  That would, of course, stop folks from getting their microarrays done, and thus deny them necessary health information that could save their lives.  So that won't work either. 

And that means the end of insurance.  Unless we're going to outlaw genetic data, and we're not, there's no way one side or the other can have access to it without destroying the whole private insurance construct.  Right now, the system operates off mutual ignorance -- we don't really know what'll happen to us, save in very broad risk outlines (we know if we eat fatty food, if we're 400 pounds, if we smoke, etc).  Give everyone hard data and the gig is up.  All that can be offered once that happens is single-payer government insurance with full risk pooling.  We all pay the same, we all get the care we need, and those who drew a genetic straight help subsidize those with a crap hand.