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What does this mean in McGee Y Utility?

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  • What does this mean in McGee Y Utility?

    I'm a little confused about the various relationship calculation models.

    I don't have any real matches at 37 markers or above. But I can have one that looks significant only on a technicality. I need to understand this.

    He is only closer if I use what they call the 'infinite alleles' calculation model. Using that, instead of the 'step-wise' model, takes off 2 from the genetic distance.

    I discovered this only when I entered our haplotypes into the McGee Y Utility.

    But it's still confusing. I'm not sure McGee is using the correct words.

    When I compare all the dictionary definitions of how each model should work, and the results of using different settings in McGee, it looks like what he calls the 'Hybrid' model returns both a genetic distance and a time to most recent common ancestor based on the step-wise model. It also looks like what McGee calls the 'Infinite Allele' model returns an infinite allele genetic distance, but a step-wise time to most recent common ancestor.

    Plus, no matter what settings you use, the caption under the time to most recent common ancestor chart says it calculated using the infinite allele method, although I'm pretty sure that's not true ever.

    This is confusing. This guy is the only could be important match so it means a lot to figure it out.

  • #2
    two different ways

    There are two different ways of counting DYS mutations.

    1)Muti-step / Genetic Distance / 'Hybrid' = counts all the mutations

    2) Infinite Allele = Since we do not know if the mutation took place in 1 Generation (Birth) or not, so if a single DYS allele has more than 1 mutation we count it at just one. You can see them in the first box colored yellow and red.

    The problem is there is no way to calculate TMRCA using the Hybrid model.

    Two off is not to far off, take a look at what DYS allele's are off more than 1, they might be fast mutating. But watch out for any RED, then the TMRCA is father back.


    • #3
      FTDNA GD already reflects Infinite Alleles calculations.
      Last edited by prairielad; 21st October 2016, 09:43 AM.


      • #4
        Neither of those replies make any sense to me.

        The first reply only repeated the definitions I already gave, but didn't explain why McGee's Y Utility calculated genetic distance at infinite alleles but time to most recent common ancestor using the step-wise method. This reply wasn't any use to me at all.

        The second response was only a theoretical explanation of the infinite allele method published by FTDNA. I am sure that FTDNA do not actually use the infinite allele method in their own databases, or this person would have appeared as a match to me there instead of me having to find it out by comparing Ysearch haplotypes at McGee. The comparison at Ysearch itself, which is run by FTDNA, clearly used the step-wise method.

        The methods are not hard to understand. What is hard to understand is why McGee does not label its settings the right way.


        • #5
          if you look very carefully at the at the TMRCA box at the bottom it says "infinite alleles" on both the infinite alleles setup and the Hybrid-mutli step setup.

          McGee labels all the analysis boxes correctly, but I have often missed them or confused them

          "I am sure that FTDNA do not actually use the infinite allele method in their own databases," YES they do, there is only one method to calculate TMRCA = Infinite Alleles


          • #6
            Originally posted by benowicz View Post
            The comparison at Ysearch itself, which is run by FTDNA, clearly used the step-wise method.
            In my estimation, YSearch is broken.
            FTDNA clearly links to it, but they do not take responsibility for "running it," and I am surprised that a monitor from FTDNA has not responded to that.
            Many of the the various alleles on YSearch are so aged, in some cases, that the newer standards for Y markers have never been updated. I now have 500 STR "markers" (includes synonyms), but not in any format that YSearch will allow me to load.


            • #7
              The language at YSearch says...

              offered by FTDNA, but whenever I have reported problems with it at FTDNA, it seems to be a linked partnership with "voluntary" maintainers, based on the responses I got.