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Archiver > DNA-R1B1C7 > 2007-07 > 1183772102


From: "David Ewing" <>
Subject: Re: [DNA-R1B1C7] FTDNA Haplogroups
Date: Fri, 6 Jul 2007 19:35:02 -0600


Yesterday, David Grierson said:

"I find myself still confused about the haplogroups assigned by FTDNA.
> FTDNA says: "* Haplogroups in *green* have been confirmed by SNP
> testing. Haplogroups in *red* have been predicted by Family Tree DNA
> based on unambiguous results in the individual's personal page." and "we
> see no reason for ordering a SNP test to confirm the Haplogroup".
>
> However, it seems to me that, in respect of the sub-clades, the FTDNA
> haplogroup tells us nothing. Take for example the three MEGONNIGIL
> results at positions 205, 206, 207 in the R1b1c7 Project. Test numbers
> 17624 and 17860 are identical at 67 positions, and 17623 has one
> difference in the haplotype at CDYb, a fast mutating position.
>
> I take it that 17624, MEGONNIGIL jnr is the son of one of the other two.
> Now 624 is M222+ tested, and shown in green as R1b1c7. The other two are
> shown as R1b1 and presumably untested. If one is the father, by
> definition he will be M222+. Why is he not so shown?
>
> Further, does this imply that any member shown in red as R1b1 might, in
> fact, be M222+? In that case, the FTDNA statement above is more or less
> meaningless, is it not?"
>

I think it is useful to distinguish those project participants who have had
haplogroup membership confirmed by SNP testing, as FtDNA does with the green
typeface. It is true, as David says, that we can be very sure, indeed
certain, that the son of a M222+ man who is also a perfect 67-marker match
with his father is also M222+, but if he hasn't been tested, we don't want
the website to report results as if he had been tested. Green type face just
means "tested."

Keep in mind that there must be some R1b1c7 folks who have had a backbone
test confirming R1b, and have not had deep clade testing confirming M222+.
These will (and should) have R1b in green, even when their haplotype is an
exact 67-marker match for the R1b1c7 modal. We may "know" that they are
R1b1c7, but if they haven't been tested, the website shouldn't show this.

David is also right that clade membership at the level of R1b conveys very
little information, but I think FtDNA is NOT saying that it is a waste of
time to do deep clade testing when they have predicted R1b based on the
haplotype, only that it is a waste of time and money to just test the SNP
that confirms membership in R1b. In our Ewing project, we have quite a
number of men who share some unique Ewing markers and are all within genetic
distance 4 of the Ewing 37-marker modal. Two men in this group of roughly 40
have been SNP tested as M222+. We think it would be a waste of time and
money to test the others, because we are "sure" that they will also prove to
be M222+. But we think it would be wrong to report them as having tested
M222+ just because we are sure what the results would be.

Where there is a problem with FtDNA reporting is on YSearch. There, some
haplogroup assignments are reported as "tested" that haven't been SNP tested
at all. I think FtDNA recognizes that there is a big problem with this, but
as far as I know, they haven't gotten around to fixing it, yet.

David Ewing

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