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Hi Shane,

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You might want to check YFull again. Currently the R-Y340824 group is empty, but it does show a sample YF131078, which I presume is yours, at R-FGC17465*.

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Since YFull only has a small number of testers compared to Family Tree DNA, not all the haplogroups are represented, and some are represented under different names. R-FGC17465 at YFull is equivalent to R-FGC17460 at YFull, since there are no FGC17465+ FGC17460- testers to form a new haplogroup. Consequently, both of you are placed in R-FGC17465=R-FGC17460, and given a TMRCA of ~2200 years.

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Cheers,

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Iain.
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Hi Shane,

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Ah, now I see the source of your confusion! :)

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If my interpretation is correct, your addition to YFull is new and the tree structure hasn't caught up with your new test. It needs to wait until the next revision of the tree before your branch is fully added.

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We know that you and Bertram share heritage below R-FGC17465, so there should be some SNPs that you share. FTDNA have found several of these, and placed you in the existing haplogroup R-FGC17460, which includes several SNPs besides FGC17460 itself, all with A... FT... or FGC... names.

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My interpretation of what YFull is showing is that they have found a new SNP, Y340824, that exists in both your test and Bertram's test, but not in the two R-FGC17464 tests. If true, this would mean you are more closely related to Bertram, and that you belong to a new haplogroup (R-Y340824) that is more recent than R-FGC17460. However, Family Tree DNA have declined to call this SNP for reasons that are not currently clear. YBrowse shows the SNP at position chrY:16,987,621.

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It's possible for me, as an administrator for the YFull R-U106 group, to go into your test and Bertram's test and look at this SNP in detail. However, it might be best to wait until the YFull tree is properly updated before I do this - their updates aren't as regular as FTDNA's.

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Regarding TMRCAs, those at FTDNA will be considerably more accurate than what is shown at YFull, even if you have do share a SNP that FTDNA doesn't recognise. This is because FTDNA takes a lot more of the Y chromosome into account with the calculation, includes Y-STRs in their calculation and (crucially) has the much larger database of testers on which to base their estimates. So I would stick with the 200 BC +/- 400 years that FTDNA offers for your relationship with Bertram instead.

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Best wishes,

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Iain.

Hi Bertram,

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If my interpretation is correct, then your interpretation is correct! There is only one SNP that would separate your common ancestor from the YFull R-FGC17460=R-FGC17465 common ancestor, so they would nominally be about 83 years younger. The actual number depends on the random nature of SNPs, so it could be centuries. If this is structure remains in the next update to YFull's tree, then we can contact FTDNA and see if they will recognise this haplogroup.

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Cheers,

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Iain.

Hi Shane,

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It looks to me like the update at YFull is not complete.

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It's impossible to have a haplogroup with one person. That rather defies the idea of a group! It's certainly not possible to define the common ancestor of one person except as themselves, so to establish a TMRCA for the haplogroup as they have done means something is amiss. That something is having other people in the haplogroup. Which other people those are, we don't yet know, but it may be you and Bertram. If that is the correct interpretation, then hold tight and they'll make further changes. Then we can see what they're up to.

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Cheers,

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Iain.

>How reliable is the tree in FTDNA?

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That depends on what you mean by "reliable". It is highly accurate, but incomplete. If you read point (1) on my recently posted message #8352, you'll see why.

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In short, any tree is only as good as the tests that make it up. FTDNA's tree is the most complete and is kept up-to-date, but it can only contain a portion of the whole story because we can only test a portion of the men who have ever lived. The tests themselves also only test a slightly different portion of each Y chromosome, so the tree does not represent all the mutations that exist, and a few individual mutations may not be in their exact positions if they are not covered in all of a haplogroup's tests.

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- Iain.

Thanks Vince,

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To expand on "may not be in their exact positions":

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It can be that mutations are only recorded in some tests both not others. This could be because some tests are the old BigY-500 tests, while others are the current BigY-700 tests. Or sometimes it's because a SNP is only picked up in some BigY-700 tests and not others. To illustrate why this is a problem, consider the following imaginary haplogroups:

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R-X1
R-X1 > X2
R-X1 > X3
R-X1 > X3 > X4
R-X1 > X3 > X5

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A SNP is found in two individuals. One is in R-X4 and one is in R-X5. So we know that at least haplogroup R-X3 should be positive for the SNP. But if no-one in R-X2 has tested positive or negative for the SNP (and no-one who is in R-X1 but not in R-X2 or R-X3 has either) then we don't know if all R-X1 are positive or negative for the SNP or not, so we don't know whether the SNP should be placed as part of R-X1 or only as part of R-X3.

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Cheers,

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Iain.

Hi Shane,

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Thanks for the update. This is the first time I've seen FTG as a SNP prefix - they're certainly racing through them. I was looking at R-FGC17460 for unrelated purposes today and note you also have a second Danish tester, presumably someone who took a Family Finder test. Coupled with the Merovingian ancient DNA this makes for an interesting story - it will be nice to see it more clearly in time!

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Cheers,

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Iain.?