[zekenie]

Agreed. Genetics is overrated and poorly understood. To be sure, nucleotide sequence is important in determining phenotype, but since the human genome project's findings were released, its become more and more clear that its no silver bullet. Protein expression, folding, and regulation are really complex systems. Very few pathologies actually come from DNA sequence. There's an entire emerging field, Epigenetics, which is basically heredity that is not the result of DNA sequence.

That blood thiner example brings up some interesting thoughts. Have they found links between specific sequences and the response to the drug? If so, this could be useful. If it is indeed really cheep to screen, it could be useful epidemiologically. It could find new associations between sequence and phenotype that weren't possible before. For example, if everyone's sequence was known, they might find that people with a certain copy of a gene didn't respond well to a certain class of drug. But, the fruits of this would come after everyone was sequenced, and after much study.

It also brings up some ethical concerns that you mentioned. What if you don't want to know you have Huntington's disease, or you are predisposed for heart disease? Or moreover, what if you don't want that information to be in a database somewhere for who-knows-who to access? These are complex issues.