I am giving this presentation at the British Isles Family History Society - USA meeting in Los Angeles today.
This kind of test may help people who are having trouble narrowing down a location in their country or county of origin.
You might be interested in the work of Dr O'Reilly in the Irish DNA Atlas Project:
Ah yes, I've read about the Atlas project. Where I read about it elsewhere it said they want 100% full-blooded Irish whose great-grandparents were all within a reasonable distance from each other...
The problem is I'm only 50% Irish and very few of my full Irish relatives are interested in contributing to something like this. :(
I may try again and mention it in my Christmas correspondence.
Oh yes, I'm a participant....but what I mean is the results eventually may be of use to research trying to pinpoint others' DNA. When we know the make up of truly Irish DNA, then it can be compared with DNA from elsewhere. It may take a while, but the RCSI has promised to release all info to participants and eventually the public.