Billie asked for comment on the following: {snip} "I sit here and read and try to figure out what DNA testing really does. I'm beginning to formulate a theory that for much more than four or five generations back it really isn't worth much at this time. If you want to know if your father is really your father it's accurate. Maybe for a couple more generation back. Back much further it kind of become hit and miss. Especially for the most common group, r1b1*. As time goes on and more and more get tested this could/will change. [ but probably not before I'm dust in the bottom of a hole. ]" {end snip} Here's my take: What DNA testing really does is to allow two persons to know that their cooperation in mutual research would be worthwhile, because their family trees intersect each other at some point -- often previously unidentified and unsuspected. DNA testing is a supplement to, and a focusing aid for, traditional documentary genealogy; DNA is not a substitute for records. Anyhow, that's how it worked for me. DNA testing led me to focus research on a family, place and time that was previously only one "possible" among many. Records and the DNA supported each other to work around a brick wall. As to the "isn't worth much" "more than four or five generations back" theory, the reverse is more the case. The further one goes back in time, the more valuable and useful DNA becomes. That is, until we hit the wall at the beginning of the genealogical time frame, when it's no longer possible to identify ancestors by names, dates, places, etc. But, OOTH, traditional "records" genealogy fizzles out at the same point. Confusion on that point may come from the many who like to talk about "genetic anthropology" rather than "genetic genealogy". To me: * Genetic genealogy is a branch &/or technique of genealogy. It is interested in individual persons and has the same purposes and similar limits to traditional genealogy. Genetic genealogists talk about "matches". * Genetic anthropology is a branch of anthropology. It is interested in groups of people and, basically, concerned with pre-history. Genetic anthropologists talk about "clades". At some point in the development of the underlying sciences, the two may converge. It probably won't be anytime soon. As more get tested, in general, what will happen is that more will find matches. The technology is very new, only a few years old, and hasn't yet achieved full acceptance. Very few projects yet have a "penetration" of more than a few dozen per million. Most are still "working out the kinks" as to goals and processes. If you have a few years left before you're in the bottom of a hole, expect great things to happen. BTW, I'm currently working up a theory that, conceptually, the probability of a match for a project participant depends on a ratio of how many "lines" (analogous to haplotypes) a project has FOUND to the total number of existing ANCESTRAL lines for the project's target population. Calling it the "F/A ratio", the closer F/A is to 1, the more probable it is that a new participant will match an existing participant. -ralpht_/)