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FTDNA HaploTree basic question

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  • FTDNA HaploTree basic question

    I have observed that many of the deep testing results for SNP's as designated on the HaploTree chart end with an asterisk designation(*), including my own (Q1a3*).
    Does this designation have a particular meaning, or indicate further testing my be necessary in the future?
    JBlack

  • #2
    The * designation indicates that the person has tested negative for all known SNPs below the SNP that determines their haplogroup/subclade. For instance, in your case, you've tested postive for M346, which defines Q1a3, but negative for all the known downstreams SNPs, mainly M3 defines Q1a3a. (That's the subclade found almost exclusively among Native Americans, which I mistakenly attributed to your results in another thread.) You can see these relationships at http://www.isogg.org/tree/ISOGG_HapgrpQ09.html

    The * designation should only be used when all the downstream SNPs have actually been tested. It should not be used when there are still known downstream SNPs left to test. Of course, if new downstream SNPs are discovered, then the * designation should be dropped, unless the new SNPs are tested for and found to be negative.

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    • #3
      Here's the official explanation from the YCC's 2002 paper: A Nomenclature System for the Tree of Human Y-Chromosomal Binary Haplogroups.

      I have bolded the key sentence.

      “Lineages that are not defined on the basis of a derived character represent interior nodes of the haplogroup tree and are potentially paraphyletic (i.e., they are comprised of basal lineages and monophyletic subclades). Thus, we suggest the term "paragroup" rather than haplogroup to describe these lineages. Paragroups are distinguished from haplogroups (i.e., monophyletic groupings) by using the * (star) symbol, which represents chromosomes belonging to a clade but not its subclades. For example, paragroup B* belongs to the B clade; however, it does not fall into haplogroup B1 or B2. … internal nodes are highly sensitive to changes in tree topology. Thus, the * symbol cautions that a given paragroup name may refer to different sets of chromosomes in succeeding versions of the phylogeny.”

      http://ycc.biosci.arizona.edu/nomenc...m/results.html

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      • #4
        Mike, has the meaning broadened since the 2002 YCC paper?

        (Perhaps I am misinterpreting what you said above.)

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        • #5
          Originally posted by gtc View Post
          Mike, has the meaning broadened since the 2002 YCC paper?

          (Perhaps I am misinterpreting what you said above.)
          I'm not sure I see any conflict between what I posted and your quote from the YCC. The description I gave is the understanding for the use of * among genetic genealogists.

          Where do you see a conflict?

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          • #6
            Originally posted by MMaddi View Post
            Where do you see a conflict?
            When you said: “The * designation should only be used when all the downstream SNPs have actually been tested. It should not be used when there are still known downstream SNPs left to test

            ... in other words, the * indicates certainty, which seems to me to be at odds with YCC's:

            Thus, the * symbol cautions that a given paragroup name may refer to different sets of chromosomes in succeeding versions of the phylogeny

            … which to my reading implies that the * indicates uncertainty, i.e. there may be new SNPs yet to be discovered.

            Again, this may be due to my misinterpretation of either or both statements.

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            • #7
              [QUOTE=gtc;177442]When you said:

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              • #8
                ^ seems to be a technical problem with the above post. I can only see "[QUOTE=gtc;177442]When you said:"

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                • #9
                  [QUOTE=gtc;177462]^ seems to be a technical problem with the above post. I can only see "
                  Originally posted by gtc View Post
                  When you said:"
                  I'm not sure what sort of glitch caused my previous post to not get posted properly, as I typed in a full answer to your post before I clicked on "Submit." Sorry about that.

                  The missing post stated that I don't see any conflict between my definition, which is the general usage among genetic genealogists, and that of ISOGG.

                  Yes, there is the uncertainty about undiscovered SNPS which may be present when an FTDNA customer tests R1b1b2*, for instance, meaning negative for all SNPs downstream of M269. But there is certainty about those downstream SNPs, since they all tested negative.

                  So, just as the YCC definition includes the understanding that the * designation includes the possibility that different haplotypes with the same name (for instance, R1b1b2*) may be of different SNP lineages because of undiscovered SNPs, genetic genealogists understand that two R1b1b2* haplotypes may not be of the same lineage. One R1b1b2* man may have an undiscovered SNP that would cause him to be recategorized as R1b1b2a, while another R1b1b2* man may have a second undiscovered SNP that causes him to be recategorized as R1b1b2b.

                  FTDNA's Walk Through the Y program and 23andMe are tools that are helping to find new SNPs and redraw the yDNA haplogroup tree. But absent discoveries of new SNPs, genetic genealogists will continue to use the * designation to separate members of a haplogroup from its known downstream subclades.

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                  • #10
                    Originally posted by MMaddi View Post
                    when an FTDNA customer tests R1b1b2*, for instance, meaning negative for all SNPs downstream of M269. But there is certainty about those downstream SNPs, since they all tested negative.
                    Thanks for coming back to this Mike.

                    The section of your reply I have quoted above precisely resolves the confusion I was encountering.

                    Good job!

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