GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2002-09 > 1031198040


From: "John F. Chandler" <>
Subject: Re: [DNA] Best DNA Test Labs
Date: Wed, 4 Sep 2002 23:54 EDT
In-Reply-To: roy.w.johnson@worldnet.att.net message <002001c2548f$161f9420$9379550c@brat> of Wed, 4 Sep 2002 21:47:37 -0600


Roy wrote:
> From reading the posts in this group, it would appear as if our Pace project
> is much more mundane than some of yours. We are not interested (at least
> not yet) in which ancient haplogroup we belong to or in theories of
> evolution.

Indeed, most projects are just as mundane, but people do like to digress
now and then.

> but there is no recorded proof. A DNA study of representatives of these
> two groups could help validate or negate the oral history.

That's the ideal setup for a study -- a simple hypothesis to test.

> Another goal would be to help current Paces to determine which line they are
> most likely descended from,

... assuming that the two lines turn out to be unrelated after all.

> and since a 25 marker Y chromosome test can
> bring the probability down to 4 generations or less, to indicate which sub
> branch would be the best area of research for such persons.

You are hoping for too much here. The 95% confidence interval on the
number of generations since the most recent common ancestor is still
almost 40 generations wide for a perfect 25/25 match. To put it
another way, if you have a collection of ten test subjects from line
#1, you might expect about 100 transmission events connecting them
all to the progenitor, meaning 2500 mutation opportunities, meaning
five mutations in all, and some of those mutations might be quite
recent. It will take a LARGE number of tests before you can build
up a general directory of mutations pinpointed to when they occurred.

John Chandler

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