[dzhu]

"Then you repeat the test."

What if the test is inherently flawed?

"look at what this drug did to my grandma"

Uh, that is purely anecdotal, n of 1 data, which is not scientifically valid evidence. This is what scientifically valid evidence begins to look like: http://www.nejm.org/doi/full/10.1056/NEJMoa1310669, which suggests the _opposite_ of what 23andMe says about warfarin sensitivity.

The point isn't that we shouldn't have tests for things such as warfarin sensitivity or statin sensitivity; it's simply that we need to have clinically VALIDATED tests for these medical conditions. Otherwise, without a clear understanding of the analytic and clinical validity of these tests, it's possible that many false positives or false negatives arise.

There's a reason why other genetic tests (e.g. Genomic Health's Oncotype DX or Myriad's BRCAnalysis) haven't been pulled by the FDA (in fact, they're not even regulated by the FDA!) - that's because they've gathered sufficient data to support the clinical outcomes and utility claims that they've made. Put more simply, these other molecular diagnostics have actually verified their science. 23andMe has not - that's why they're being regulated.

[girvo]

You mean what if the doctors second test is inherently flawed? Then you're screwed either way :/