The trick to it is the few who did arrived at the same time the Brits were imposing strict enclosure and rent laws.
Consequently, as native folk were being driven out of their homes to live on the roads the Roma were there to teach them how to do it.
So, you think that some DNA tests ought to be done on these Black Irish in Ga and SC who act so Gypsy? Sounds like a great idea--fascinating, even. We could place bets--and my bet is that there's some shared ancestry.