you are still searching an entire data base. There are privacy concerns were those who have their DNA on file with these businesses.
Their records are protected. Did you not read the TOS I posted? It claims their clients are protected. I'd be pissed if the cops showed up on my doorstep under these conditions, asking questions about some remote cousin I have no awareness of. There's a law suit in the works right there, because my lawyer would ask one question: How did you end up on my client's porch?
But you would still need a warrant to search these data bases.
...and you would still need everyone to register their DNA with who, which data base? Since there are more than one...
It still boils down to Muellerism.
It actually falls under warrantless searches. You are cruising data bases without consent of the clients. This information is NOT public as indicated by TOS.