The rub is that appeals to authority are a logical fallacy to begin with, something I would assume an educated person would know, so not use one. The issue has to be whether the conclusions drawn from the test results are valid - and if not, why not - not over the credentials of who made them. He didn't address the actual issue, at all. I mean, if he thinks a GD of 16 at 67 markers (30 at 111 markers) is a match, he needs to give the basis for such an assertion, not just tell me I'm wrong. Diana **************************** Not necessarily--authority is rather like any sort of label--the quality of the underlying product guarantees the label, and not the other way around. I'd ask him to explain why he thinks that a GD of 16 or 30 implies a relationship within genealogical time when no one else in the field would agree--that is, if you decide he's worth trying to convert. He won't give a reason, of course, because he doesn't have one--he had hoped instead to scare you with his credentials, and that is what I found so amusing. I've had one bad experience of this kind, but it involved different Haplogroups and not GD; however, that story ended as well as such a story can end and the family in question is still active in my project. Some take it hard when they discover that their line isn't what they thought it was or what their research indicated, and the unexpected result leaves scars that never go away, while others take the shock in stride and recover quickly. I've often wondered how I would have reacted if I've uncovered a break in my line. Lindsey