A small search surfaces a lot of gene banks which store human and non-human DNA. Use your favorite search engine for this.
Generally submissions are done with patients' consent, but I'm not very sure that some of the blood samples are directed to national private databases for countries' own use and research.
The reasons doesn't have to be nefarious. Knowing your population's genetic weaknesses is a good way to defend it, and having access to a wide pool allows a deeper understanding of genetic conditions and how genetic therapies are working.
Also, earlier comments than mine already cited how law enforcement in US is already using this as evidence.
I'm an ordinary person. I don't have access to more information than you do.
https://www.cbc.ca/news/world/dna-from-genealogy-site-used-t....
Also, the government keeps all DNA from people arrested (not convicted) for anything
https://www.nbcnews.com/news/world/your-dna-police-database-...
> Which governments are you referring to?
Any that has an intelligence service. (And probably most others too.)
> And how are they doing this?
They get the data from breaches like this or otherwise purchased from services like this.
> And how do you know of this?
I’d suspect less that they know and more that they have a reasonable suspicion. I personally have that suspicion because 1) it’s feasible and 2) governments would be interested in the data.
https://www.masslive.com/news/2024/01/how-to-get-a-free-gene...
one of these is not like the other
It's easy to throw out cynical opinions. It's also easy to come along later and say "I _knew_ this would happen"
If one outcome is 99% likely and the other 1%, the intelligent thing is choosing the 99% likelihood, but that still means that sometimes the person making the bad choice was right.
That doesn't make them intelligent, it makes them lucky.