I have an ancestor that I'm sure of, Robert Alexander b.1789, and what I have found says in Tyrone, Ireland. Someone on Rootsweb shows his father as William James Alexander born about 1737 in Ireland. I don't see these names on your list, but I'm wondering if they are names you are aware of? This is well back in my tree and it isn't my surename. So, we dont have any way to connect with DNA. But we are still looking.