I'm surprised with all the DNA testing that's out there now, that they don't test some of those descendants. Maybe they have?
DNA testing would be quite an undertaking. I don't know of any confirmed gravesites of colonists, so I'd think you'd have to track down their descendants in England, in addition to tracking down likely populations in NC. And, it could get more complicated than even that, since several of the native tribal "kings" in the area first came there via the whaling trade, and were originally from Nantucket. Ocracoke Inlet was the southernmost port, as I understand it. It's possible that whole tribes came down. The population was not static. And then you have the persistent tales from the 1600s of blue eyed "indians" in the mountains, who could understand at least some English. It's quite the tangle, and is likely to remain something of a mystery.