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Are these FF results typical?

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  • Are these FF results typical?

    Of 61 of my FF matches who have declared their Y haplogroup only one is a fellow R1a which seems a bit strange to me considering these folk are supposed to be related.

    There are:-
    35 R1b; 17 I; 5 E1; 2 G; 1 Q and 1 R1a.

    I'd like to know from any R1as whether or not they have similar results?

  • #2
    Originally posted by royfarnol View Post
    Of 61 of my FF matches who have declared their Y haplogroup only one is a fellow R1a which seems a bit strange to me considering these folk are supposed to be related.
    Your Y haplogroup is inherited from just one string of your ancestors - your father's father's father's.........father. But your autosomal DNA (which is what FF uses) potentially comes from all of your ancestors. So, of your 64 great, great, great, great grandparents, your FF matches could come from the descendants of any of the 64. And only one of those 64 necessarily has the same haplogroup as you, for the other 63 they could belong to any haplogroup.

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    • #3
      Originally posted by fbirder View Post
      Your Y haplogroup is inherited from just one string of your ancestors - your father's father's father's.........father. But your autosomal DNA (which is what FF uses) potentially comes from all of your ancestors. So, of your 64 great, great, great, great grandparents, your FF matches could come from the descendants of any of the 64. And only one of those 64 necessarily has the same haplogroup as you, for the other 63 they could belong to any haplogroup.
      and most of the descendants of the one of those 64 who is your y-DNA ancestor will have a different y-hg - and of course 1/2 of all your FF matches will have no y-DNA at all!

      and it increasingly seems likely that many if not most of our autosomal matches share MRCAs with us further back than the generation-of-64. it seems clear, doesn't it?, that the vast majority of our matches are 5th - nth cousins... and to the extent that is true, we're talking 128, 256 and more ancestors-to-be-descended from with our matches. in short, the sheer numbers of ancestors from which our matches are descended make it unlikely to have an autosomal match with a male on your patrilineal line show up among your matches.

      and of course it all depends so much on who tests. a perhaps more interesting exercise would be to look at people who are y-DNA matches and have both done the FF test, how many are matches? I haven't gotten out the calculator, but presumably you'd have to be a 65/67 match or better to have any reasonable shot at all, statistically speaking, at being a FF match.

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      • #4
        Relatively few of my FamilyFinder cousins have the same Y DNA haplogroup type as me (we'll call it "G", to be brief here). Quite a few of my FF cousins do carry a "R" Y DNA haplogroup though.

        The previous posters are very correct. The Y haplogroup comes from our respective direct male line. So for me, whenever I see a cousins with a G haplogroup similar to mine I immediately take notice; there's the possibility that person may be from my own direct male line (directly related to the line associated with my father, paternal grandfather, his father, etc.).

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        • #5
          I am trying to talk my closest 67-marker y-dna matches into ordering the Family Finder test. None of them has ordered it yet, and I think it could be very informative.

          But I realize the various y-dna lines of my current FF matches may not be part of my ancestral mix at all; they could represent other lines outside the line or lines that connect my matches and me. It all depends upon where the connection is.

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          • #6
            I think FF has the potential to really help resolve the more recent generations of y-DNA matches. At 66 out of 67 markers, the best that y-DNA can do is say that you have a MRCA within the last 250 to 300 years. That isn't saying much. If you also share an FF match, you can get a better idea of just how close you really are.

            FF works best on closer relationships. Y-DNA & mtDNA are the opposite & work best on the most ancient of connections.

            Timothy Peterman

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            • #7
              I hope this doesn't stray too far from the original topic "Are these FF results typical."

              I just got a recent match with 8 segments. Seven are typical - 500 to 600 snps, but one is 10,396 snps! I don't have anything like this large a segment in my other 178 matches. The suggested reationship is 4th cousin (Cl 3-5).

              Is this an extraordinary segment or do others have similar resuts?

              Jim

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              • #8
                Originally posted by Beeswax View Post
                I hope this doesn't stray too far from the original topic "Are these FF results typical."

                I just got a recent match with 8 segments. Seven are typical - 500 to 600 snps, but one is 10,396 snps! I don't have anything like this large a segment in my other 178 matches. The suggested reationship is 4th cousin (Cl 3-5).

                Is this an extraordinary segment or do others have similar resuts?
                The number of SNPs doesn't directly correlate to the length in centimorgans (cM). How many cM are those segments? That's a better measure of how significant a shared segment is, because some areas on the chromosomes are more susceptible to recombination than others.

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                • #9
                  The large segment is 20.46 cM. The other 7 are in the 1-2 cM.

                  Jim

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                  • #10
                    Segment length vs value

                    A segment of 20 cM is long enough to be a solid match
                    and yes they are common
                    Segments up to the full length of a chromosome are routinely found
                    in parent/child and even grandparent/grandchild

                    Any segment less the 7 cM is suspect of being just random
                    even if it has more the 500 or 700 SNPs

                    I think any segment less than 5 cM should not be used in
                    the sum of segments nor the segment count.
                    My research shows that at 5 cM 80% of the segments
                    fail to match when the atDNA is "phased"
                    Thus the were just random Identical By State and not
                    Identical By Descent

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                    • #11
                      Originally posted by royfarnol View Post
                      Of 61 of my FF matches who have declared their Y haplogroup only one is a fellow R1a which seems a bit strange to me considering these folk are supposed to be related.

                      There are:-
                      35 R1b; 17 I; 5 E1; 2 G; 1 Q and 1 R1a.

                      I'd like to know from any R1as whether or not they have similar results?
                      Yes.

                      As others have pointed out, YDNA haplogroups are not meaningful with regard to autosomal DNA matches due to different inheritance patterns and patrilineal line only representing small fraction of your ancestors. Same applies to mtDNA. In both cases, any trends among matches are more likely in line with representation in general population or populations that your ancestors were part of. Besides females not having Y, you and autosomal cousin may have common ancestors along lines not associated with either of your Y DNA ancestors.

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