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How does this work?

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  • How does this work?

    I just got (initial) BigY700 results for a kit I'm managing. This is my first time going through this, so bear with me if I'm not quite getting it, but: Is it possible that there some additional information that will be posted to my basic results within the next few weeks?

    Here's what I mean: I have two BigY700 matches registered who are on different branches of the same subclade. One of them I don't take too seriously because they have a profile on the Big Tree project, and I share none of the SNPs that define their branch under our clade. From what I can tell, it looks like I just share a bunch of low-quality SNPs with them that I can just ignore.

    However, the other guy also has a Big Tree profile, and I share 5 SNPs that define their block under the overall clade, so I assume there is something real going on there. There are two problems, though:

    1. The Block Tree doesn't yet show us segregated within a new block. I'm not super worried about that because I figure it might take FTDNA a while to update that information. Is that right?

    2. My currently published results don't show any results at all for 11 of the 29 SNPs that define this guy's terminal block per the Big Tree. I've checked listings for all reported SNPs, positive, negative and no-call, indexed both by location and name. I've also scoured the web to see if there are alternative names for some of those SNPs--for some reason, the list FTDNA gave me doesn't report locations for all named SNPs. No dice.

    Will FTDNA revisit and resolve these important no-calls? Why wouldn't I have reported results for those 11 SNPs? I know for a fact that this guy tested at FTDNA, so I don't understand why they would be missing from my list. Are they really done testing everything?

  • #2
    Just for reference, here are the 11 named SNPs I can't find on my list:

    I forgot to mention another 2 unnamed SNPs in my original post. Here are the hg38 locations:


    • #3
      Another point of clarification: The Block Tree says that there are an average of 18 private variants between me and this guy, which maybe not coincidentally is exactly the number of SNPs appearing on my results list which also appear on the list of 29 defining SNPs for this guy's Big Tree profile.

      So is the deal possibly that:

      1. FTDNA no longer tests the SNPs "missing" from my testing list, probably because they are no longer considered to be of high quality, and that I can therefor ignore them?

      2. FTDNA will adjust that private variant number later on, when they update the Block Tree?

      Also, what is the current best estimate mutation rate for the average, high quality FTDNA SNP? I don't see any TMRCA estimates posted on my results, and anecdotally I've heard figures of 85 years or 150 years, which obviously produces really widely divergent estimates.


      • #4
        Okay, I think I've just answered my most urgent questions myself. The SNPs I share with this new guy that I thought were going to define a new block are allocated differently by FTDNA and the Big Tree. FTDNA makes them all parts of the parent block. Meaning--if I assume FTDNA is correct--that my results are totally undifferentiated underneath the parental clade, and I learn absolutely nothing new. Line of inquiry ended right there.

        That's kind of shocking that the Big Tree could diverge so much from FTDNA. I can only assume this is the result of Big Tree participants testing at different resolutions, and not carrying forward any updates from FTDNA.

        I'm still curious as to why my results don't list some of the SNPs depicted at Big Tree, but I get the feeling that it's because they changed their mind about the reliability of some of the SNPs and stopped testing. If that's the case, I don't think I care.

        But I do care about what the current consensus is about the average mutation rate. That's fundamental.