[krageon]

Anonymization doesn't work in practice (people are bad at it and don't understand how to do it), and it definitely doesn't work on DNA. So in order of claims: You shouldn't trust it was done well and if someone claims that they did this for your DNA they are lying. Why wouldn't you want to opt-out from having some of your most sensitive information used by someone who is willing to lie to get access to it?

The alternative to "they are lying" is "they are too incompetent to make the claim" and I'm honestly not sure which is more worrying. You can take your pick, they're both more or less equally terrifying.