The Economist recently published a piece about the impact of the genome on the insurance industry.
This was all very interesting, but I felt it didn't quite tackle the real issue: Once we know a lot, we will have to be more explicit in what medical care we pay for and what medical care we do not pay for, as a society (or in each country). Insurers are simply the bearers of the bad news, because they have the data. Previously, they let us spread the ignorance; but now, they know too much. They will allocate according risks according to their knowledge, or ask us as a society to make decisions about what to pay for.
If we do not allow insurers to use the data they have, they may decide not to play. If we force them to play, they will force us to pay the costs - either in increased rates for everyone, or in restrictions on coverage... or in the knowledge that we will withhold treatment from certain diseases, kinds of people (over 80, refused to stop smoking, etc.).
Knowledge will not set us free; it will make us take on and acknowledge responsibility for what was once left to local decision-makers, chance, markets and other less explicit forces.
But the article also assumes that knowing someone's genome means knowing that person's destiny. As the author quotes Brandeis professor Dr. Stephen Cecchetti: "And once you have perfect information,....it will be the death of insurance, which depends on uncertainty and pooled risk." Fair enough, but perfect genetic information is not perfect information about people's fates.
It is, however, clear enough that it will force us to be much more explicit about what risks we will cover and what responsibilities society will force back onto individuals.
Full disclosure, of sorts: I'm part of the Personal Genome Project, run by George Church and described in this subscription-required (sorry!) op-ed in the Wall Street Journal. One reason I'm part of the project (publishing my genome and health records for all to see) is that I want people to start addressing these questions now, when we still have time to think rationally.