I think I mispoke, and used the wrong word. I see what you mean about "diluted." What I meant is that the Y-DNA gets mixed and traits are dropped, added, depending on the recessiveness or dominance of the trait. So that brings up another thing, that is that there is a difference in speaking about the dna that is used for genealogical matches, and the dna that transfers certain traits. I'm not all that up on what that difference is, but I know that they are different. Maybe someone can speak to that? And, I think it is important to say here, that dna testing is but one more tool for the genealogist. It is not the only one! It's just the most advanced technologically speaking. It is an important tool, in my opinion, for people who may be adopted, or for other reasons have no clue about their ethnicity. It adds icing to the cake for people who know their ethnicity and through dna can determine which sept, clan, haplogroup they belong to, even the common ancestor they share with someone else. It just depends on how much you want to know about your ancestry. For some, it's enough to know their immediate families, others want to know more, and for many it can become an obsession. To know where and who you came from is to know about yourself. There is a certain longing to belong, I think, that is inherent with being human. Even animals seek out others of their own kind. I think Irish descendants have this longing even more than other ethnicities. Wonder why that is? Is it something bred into our genes? Whoever the Irish are, wherever they got their genetic makeup from, they have produced a most beautiful culture. Peace Phyllis >Phyllis wrote: QUOTE: <It's true that Y-DNA is "diluted" after so many generations. But >depending on the number of markers tested and compared, it is still a >pretty good predictor of possible paternal ancestry. It can't "name" a >person as a male's paternal ancestor, it only shows who, in his >lineage, could have been a common ancestor to another person with the same >results as his.> > > I'm not sure, but this sounds to me like you're suggesting that the Y-DNA is fragile, whereas I thought that the mtDNA is the more fragile one. As it is, the whole Y-DNA sequence is not diluted...it is only certain markers within the sequence that are subject to "rapid" mutation. Scientists know which markers these are, and you can see this information within the Family Tree DNA site. > >