Announcement

Collapse
No announcement yet.

Understanding haplogroups

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Understanding haplogroups

    I am confused as to how to match the lettered Haplogroups used on these pages with the numbered Haplogroups used elsewhere. There seem to be multiple overlapping systems of nomenclature. I tried to make some sense of the YCC lists (a link on the FTDNA page) in Dr. Hammer's article, but I am still quite at a loss to understand. FOr example, the Seven Daughters of Eve use letters (H,I,J, U etc) for mtdna, and other books and articles use M's . There are also designations such as R1b or E3b for Y's or designations like hg1 or hg9. Does anyone have a relatively simple explanation or cross reference? I am not a geneticist.

    Additional question: I am the GA for the Whitney surname project. As of now, we have 4 distinct lines, two of which appear to be unique (so far). One of the unique line people has some exact Y 12-marker matches from the database (not the project participants). Are those people likely to be related in a meaningful way? Would it be worth his while to "go public" and see? Or should he first do a 25 marker test, and what is the probability of those 25-marker matches being related (if they match). I don't want to encourage family members to get tested if the results are not useful for the project.

  • #2
    Re: Understanding haplogroups

    Originally posted by whitkeen
    I am confused as to how to match the lettered Haplogroups used on these pages with the numbered Haplogroups used elsewhere. There seem to be multiple overlapping systems of nomenclature. I tried to make some sense of the YCC lists (a link on the FTDNA page) in Dr. Hammer's article, but I am still quite at a loss to understand. FOr example, the Seven Daughters of Eve use letters (H,I,J, U etc) for mtdna, and other books and articles use M's . There are also designations such as R1b or E3b for Y's or designations like hg1 or hg9. Does anyone have a relatively simple explanation or cross reference? I am not a geneticist.

    Additional question: I am the GA for the Whitney surname project. As of now, we have 4 distinct lines, two of which appear to be unique (so far). One of the unique line people has some exact Y 12-marker matches from the database (not the project participants). Are those people likely to be related in a meaningful way? Would it be worth his while to "go public" and see? Or should he first do a 25 marker test, and what is the probability of those 25-marker matches being related (if they match). I don't want to encourage family members to get tested if the results are not useful for the project.
    Question 1: The Haplogroup letters for the Y-DNA are unrelated to those of the mtDNA. Therefore, the definitions that we offer for the Y-DNA haplogroups cannot be used for the mtDNA. You can find an interesting study about mtDNA Haplogroups at the following link:
    http://www.journals.uchicago.edu/AJH...53/970153.html For a better understanding of the Y-DNA nomenclature our suggestion is: http://ycc.biosci.arizona.edu/

    Question 2: Depending on the Haplogroup, a 12 marker match may not be meaningfull and therefore we recommend going to the 25-marker test. This is the case with R1b, for example, where there are many 12-marker matches without a common ancestor. In general, a 12 marker mismatch is of course a sign that no further refinement is needed. And you would want to go to the 25-marker test to confirm the first results in case of a match whatever is the Haplogroup. There are those who view it as some sort of confirmation process. (or adversely, an elimination process).
    Max Blankfeld
    Vice-President and COO @ Family Tree DNA
    A Gene by Gene Company

    Comment


    • #3
      Thank you Max. I am aware that the haplogroups for Y are unrelated to the haplogroups for mtdna. While the surname project is only Y, my husband did both and has 2 different haplogroups. I was just trying to understand where the various Y groups are identical, and where the various mtdna goups are identical. I will check out the articles you mention, but the YCC article (for Y-DNA) that you link to on the home page is not clear to an amateur like me.

      Comment


      • #4
        Re: Understanding haplogroups

        Regarding Y groups:

        I understand your confusion. FTDNA is using the "new" system (approved by the YCC) but many folks are still using an older system (HG2, HG2, etc.).

        So - my former HG1 participants are now R1b.

        My project is new and my participants don't seem to care about haplogroups (they just want matches) so I just have the "new" group on my results page. However, if it became a problem, I'd add a column and put in the "old - HG" number too. The "old" number is pretty easy to figure out (using Garvey's guidelines). The "nomenclature" link at the ycc Arizona site has an intimidating chart with the new ycc groups and includes 7 other earlier naming systems! So we are not just talking about two systems.

        I'm sticking with the FTDNA (ycc approved) designation.

        G.
        Last edited by GKBopp; 16th April 2003, 11:18 AM.

        Comment


        • #5
          Thanks. I agree, the YCC "cross reference" is very confusing, at least to me as a non-geneticist. What are the "old" HG numbers and who and what are "Garvey's guidelines"? The trouble is in reading books on the subject, we get Y groups like hg1, and R1b and Mutation numbers and for mtdna, Mutation numbers and letter haplogroups like U or J. Is there anyone who can put it all into a cross-reference chart? I didn't even know that R1b is HG1 and is HG1 the same as hg1? I would like to stick with FTDNA designations, but would like to be able to make the connection to other people's research and publications.

          Comment


          • #6
            Originally posted by whitkeen
            Thanks. I agree, the YCC "cross reference" is very confusing, at least to me as a non-geneticist. What are the "old" HG numbers and who and what are "Garvey's guidelines"? The trouble is in reading books on the subject, we get Y groups like hg1, and R1b and Mutation numbers and for mtdna, Mutation numbers and letter haplogroups like U or J. Is there anyone who can put it all into a cross-reference chart? I didn't even know that R1b is HG1 and is HG1 the same as hg1? I would like to stick with FTDNA designations, but would like to be able to make the connection to other people's research and publications.
            Regarding the Y chromosome testing:

            There's a link to Garvey on my below page:

            http://freepages.genealogy.rootsweb....aplogroups.htm

            Keep in mind that true haplogroups are determined by SNPs not the STR's used in the Y studies. The haplogroup info from FTDNA is an estimate based on the STRs. Don't forget that we are participating in the infancy of a new technology here - so things are going to keep changing, some things will turn out to be wrong, etc. Frankly, I don't think it is wise to put too much emphasis on haplogroups at all at this stage in the game.

            G.

            Comment

            Working...
            X