Which is not really an ironclad guarantee it won't happen (I'm thinking in terms of the law being modified or repealed, not in terms of companies ignoring it).
But the solution to the insurance problem is pretty obviously at the societal level. Once the testing is cheap enough, if they are allowed to, companies will just refuse carriage to people that won't submit the DNA (well, assuming that DNA profiling provides meaningful pricing information).
I don't think repeal of GINA is remotely likely, just look at the political discussion about pre-existing conditions on both sides of the aisle, there is no appetite for having companies accurately price insurance.
I think the fact that health insurance premiums are the #1 thing brought up in privacy discussions is basically evidence of the fact that we all know that insurance is a bad model for healthcare, but we can't bear to socialize it yet.
But the solution to the insurance problem is pretty obviously at the societal level. Once the testing is cheap enough, if they are allowed to, companies will just refuse carriage to people that won't submit the DNA (well, assuming that DNA profiling provides meaningful pricing information).