GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2005-12 > 1134871943
From: steven perkins <>
Subject: Re: [DNA] RE: Are you missing the Geno boat?
Date: Sat, 17 Dec 2005 20:12:23 -0600
References: <NFBBJIGLNLMGJIOLOGFBOEHMGBAA.email@example.com> <BAY106-DAV157A48568D70F1B1B4CC90B33D0@phx.gbl> <REME20051217205026@alum.mit.edu>
While John is largely correct that 12 marker results is all that is
needed to verify or refute certain hypothses for genealogy work, there
are exceptions. My Perkins, Creekmore, May, and McDaniel ancestors
are all 12/12 matches. It is only by testing at 25 and 37 markers
that they can be shown to be distinct lines. Even there, the McDaniel
line is a 36/37 match, but not known to be in geographical proximity
at a common time, so they are still distinct for genealogy purposes.
Steven C. Perkins
On 12/17/05, John Chandler <> wrote:
> Herb wrote:
> > To just stop and look at 12 and even 25 markers, in our experience
> > is really a waste, and not an indication of your desire to know your
> > family. 37 marker testing has proven from our small sampling of
> > only 50 people (23 different groups) so far is the only way to make
> > family connections. In fact we are questioning if 37 markers are
> > enough to separate out various members of a family.
> It all depends on what you want the DNA testing to accomplish. If you
> want the testing to find not only who is related but also what the
> exact relationships are, you're out of luck because it would take on
> the order of 1,000 microsatellites (STR markers) to get that kind of
> resolution. Unfortunately, the Human Genome Project has revealed that
> the euchromatic portion of the Y chromosome has only about 200
> microsatellites in all. Fortunately, there is another approach --
> when it becomes economically feasible to sequence the entire
> chromosome for the hobbyist customer, we can go ahead and reconstruct
> the (male) human family tree directly.
> Coming back to the present day, we must recognize that the current
> capabilities of DNA testing are limited to "pointing the way" for
> conventional genealogy and/or confirming or refuting the conventional
> research already accomplished. For the latter, it is often enough to
> test 12 markers.
> John Chandler
> Search Family and Local Histories for stories about your family and the
> areas they lived. Over 85 million names added in the last 12 months.
> Learn more: http://www.ancestry.com/s13966/rd.ashx
Steven C. Perkins