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Archiver > GENEALOGY-DNA > 2005-06 > 1119044386


From: "" <>
Subject: Re: [DNA] I am M269+ (R1b1c)
Date: Fri, 17 Jun 2005 17:39:46 -0400


If you are P25+ you are definitely R1b1 -- for the moment. Clade labels
change in this game.

Three years ago, when the YCC tree was first published, P25 identified R1b.
But then a new SNP was discovered -- M343 -- that was intermediate between
M173 and P25. That pushed P25 and all the downstream markers one rung
further down the ladder. That meant P25 became the designator for R1b1,
where it remains today.

The haplogroup tree is periodically revised as new SNPs are discovered and
inserted and old SNPs are moved to different levels in the hierarchy based
on new evidence. But regardless of what happens to the tree, the SNP
designations never change. If you are P25 this year, you will be P25 next
year. That's why some people think it is easier to talk about haplogroups
by their SNP rather than by their clade designation within the tree.

As to why some companies test for this marker and some for that one to
establish a particular spot in the hierarchy -- I dunno. Inertia, maybe, in
the case of the labs that keep testing something that worked just fine in
the years before the new SNPs were recognized. The purist in me thinks that
a lab should always test for the most recent (= downstream) SNP that can be
associated with a particular clade. For the broad R1b universe in our
current state of knowledge, that SNP would be M269. But since it appears
there would be something like 99.9 percent overlap (or even higher) if you
tested a European population for both SNPs, it is almost a distinction
without a difference.

A side note here: Because the clade labels keep changing, you need to make
sure you know the date of a particular study you are reading. If you read a
2003 study that refers to haplogroup R1b3f, you need to know that will be
R1b1c6 in the current 2005 terminology. (That's a subclade of R1b1c that is
found in Iberia.) A year before that it had been called R1b8. But in any
case, it is always the subclade identified by M167 (also called SRY2627).

In 2002, the clade called R1b1 was associated with M18. Today, R1b1 is
associated with P25. If you don't know your SNPs and you're trying to
compare the findings of clade-oriented articles published a couple of years
apart, you could get onto the wrong branch of the tree pretty quickly if
you aren't paying attention.

David W.


Original Message:
-----------------
From: Robert Davenport
Date: Fri, 17 Jun 2005 13:53:41 -0700
To:
Subject: Re: [DNA] I am M269+ (R1b1c)


So, if you are P25+, like me, you are definitely Rlb1.

Why don't they test for M269? At this point, I can only "surmise" that I
have it.









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