[me_me_me]

I am not sure, only guessing. But why would they ask for permission in the firs place?

> They already did something with my biological samples

I can only guess you were tested for something in the hospital. Samples are sent to the lab (separate department) to be tested. If additional tests need to be perform they can use the blood they already received. The samples are kept for ready availability if additional tests are requested by doctor. Doctors dont care how its done, they dont have time to inform lab patient x is out home.

After some time they need to be destroyed - due to expiry date on it. Before destroying the lab contacted you and asked for dna permission.

> And also - could eg. police use it?

I don't know that. But you might want to check how medical data is protected in your jurisdiction.

[dekhn]

They asked for permission because if you want to use data a hospital already has stored for another use, you need to contact the patient to get additional consent (you already gave them consent to collect and keep the sample).

See https://www.hhs.gov/ohrp/regulations-and-policy/guidance/faq... under "Should the initial consent ... be repeated or supplemented?" and I think this is the law: (45 CFR 46.116(b)(5)).