GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2002-10 > 1035572220


From: "John F. Chandler" <>
Subject: Re: [DNA] DYS Numbers and Mutations
Date: Fri, 25 Oct 2002 14:57 EDT
In-Reply-To: azjrh@msn.com message <003901c27c24$32b84840$0201a8c0@msn.com> of Fri, 25 Oct 2002 06:42:50 -0600


Jim wrote:
> I can't imagine the DNA retailers pooling resources anytime in the near
> future.

Not likely... I wasn't pinning my hopes on that.

> Maybe "someone" could encourage each of the retailers to pool their data,
> and provide it to one person, who could develop mutation rate for each DYS.

Indeed, the retailers do not have the necessary information, except for
the Special Cases at BYU. In fact, the experience of the Rices with
BYU/Sorenson suggests that the retailers can't be expected to get the
genealogical details right, even if the lineages are supplied along
with the DNA samples. No, I think the answer is cooperation among
the many project coordinators.

> Last thought: Will the www.ybase.org [Alastair Greenshield] database help
> in this pooling effort, and eventually someone with your knowledge [and
> others at this list] will be able to take the data and develop
> contemporaneous mutation rates?

What's needed is a descendancy chart connecting all the test subjects
in each family, so that the total number of transmission events can be
counted and (just as important) so that the actual number of independent
mutations can be counted. For example, the Strickland study included
three brothers who all have the same haplotype (which includes a one-step
difference at DYS449) -- all three together are evidence of only one
mutation, not three, and, although the first brother brings in 8
transmission events to the tally, each succeeding brother brings in
only one more.

> As for now, I would like to do whatever I can to contribute to this pooling
> effort, which you suggested.

The Strickland web site has just the right approach, as far as enabling
outsiders to mine the data is concerned. It has a virtually complete
set of descendancy charts (just one testee is omitted, and that one is
clearly not related to the other Stricklands anyhow). The charts
suppress the names of living persons, but that's ok, since place
holders are given to allow the reader to count up transmission events.

Of course, it would have been just as good to give a discussion of
the results, identifying which Stricklands are actually traced to the
known progenitors, giving the tallies of transmission events, and
mentioning which apparent mutations are actually independent. That's
what I did with the Rice and Blanchard studies.

It's unfortunate that the Strickland results are clouded by uncertainty
over the uncalibrated loci, but one can hope that that will be cleared
up in time.

John Chandler


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