Having written in the last year a widely discussed paper about Informed Consent the new WMA revision #25 makes this rather waste paper:

For medical research using identifiable human material or data, physicians must normally seek consent for the collection, analysis, storage and/or reuse. There may be situations where consent would be impossible or impractical to obtain for such research or would pose a threat to the validity of the research. In such situations the research may be done only after consideration and approval of a research ethics committee.

With this paragraph in effect you can now to do every test on every sample that you possess. I will tell you from my practical experience how this work

1. Declare a (fake) limited scope of a study to your probands.
2. After 2 or 3 years extend the scope to something else like a GWAs or metabolome profile.
3. Declare to yourself that it is impractical to obtain consent for such research and it would pose a threat to your careeer for not doing this study.
4. Your colleagues at the LEK will understand that, LOL.

yea, yea.