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Archiver > GENEALOGY-DNA > 2002-04 > 1019689522


From: "Allan S. Gleason" <>
Subject: Re: [DNA] Relative Genetics/Ancestry.com results
Date: Wed, 24 Apr 2002 16:05:27 -0700
References: <JCHBN.020424.133126.RC0@CUVMB.CC.COLUMBIA.EDU>


That is all very true, John, but one doesn't or shouldn't publish until one has
something to publish. Show me something about this genealogical DNA stuff that
isn't still experimental. How many true genealogy oriented DNA papers have been
published by anyone? I see URLs for the same papers over and over again. Perhaps
Woodward is sticking his neck out more than the others - Sykes on the other hand
doesn't seem to be doing anything except writing books. Is he waiting for someone
else to do the work? You'll note that DYS310 is no longer used by BYU/Rel.Gen.
either. We knew when we got the FREE analysis that we were experimental - remember?

Regarding the BYU project, we don't really know what they're doing with the samples
and data "in house," do we? We only know what they plan to do with it publicly -
sort of. As you well know, John, I'm pretty dense so I think they could explain it
to me perhaps three more times and I still wouldn't understand exactly what the
program is all about. No, John, don't tell me - I'll wait until it comes out in
paperback! <g> Regarding my mental slowness, I'm still trying to understand why
people are so interested in trying to "match" the forensics and now the two lab
databases none of which have significant populations? To what purpose? I'm still
upset that I matched up with some geezer in Berlin who is probably in prison as a
wife-beating alcoholic - or worse.

As I mentioned in my earlier, Diahan mentioned to me a rate of 0.0025 and I later
calculated the results of our tiny study - certainly not scientifically significant
- was 0.0030 so with the new markers, I'm not surprised at the more rapid mutation
rates being quoted. I might make the additional comment that there is little
incentive to change the rates beyond those established (0.002) because the only
people (customers) in the genealogical community who are really concerned about the
rates are those who are looking for a completely unknown common ancestor (perhaps
using Ann's calculator). And how would they be able to know whether the rate is
right or wrong? So a few get too many mutations and get dropped from the family
tree, so what! The lab got its money. In my study, the rate could have been .001
or .005 and it wouldn't have made any difference since we weren't relying upon
mutations. All we cared was that we didn't get too many mutations to fit our
genealogies, otherwise the more the merrier! The siblings didn't have any mutations
between them and the rest of us got one different mutation apiece which was peachy
keen! I do have one suggestion. Rather than fall out of your genealogy tree, use
Ann's calculator and change the mutation rate until you get the number of
generations (or time period) which fit your (possibly hypothetical) data. Then
everybody is happy! Perhaps Ann could rewrite her calculator to calculate the real
unknown based upon the genealogical evidence.

Allan







"John F. Chandler" wrote:

> Brett wrote:
> > This is an in-house number based on research...
>
> "In-house" research that has not been published is always suspect.
> The system of publishing results is not for the purpose of revealing
> interesting facts -- it also allows reviewers to shoot down obvious
> mistakes before publication and competitors to offer contrary evidence
> afterwards. Here is just one example of a possible mistake that could
> be affecting the "in-house" results: last year, the BYU studies
> included a marker they called "E5" and which has since been revealed
> to be the same as DYS310, which no other lab has used for genealogical
> tests. It was clear from the results (assuming that they were, in fact,
> correct) that the mutation rate for that marker is MUCH higher than for
> any of the others. In a study that included descendants of a single
> common ancestor, with 98 total meioses, there was no clear majority of
> any one allele among the descendants, and five different alleles turned
> up. Since we were not told the actual repeat counts for the arbitrary
> "scores" in the report, it is impossible for me to determine the actual
> number of mutations, but it had to be at least 6, and at least 2 of
> those had to be double, and 1 triple! Thus, the estimated mutation rate
> had to be at least 10% (+/- 3%). This is close to two orders of
> magnitude higher than the "standard" rate and is so high that it no
> longer qualifies as a "rare" event, which means that we should expect
> some of the supposedly unmutated alleles to be the result of multiple
> mutations that happen to cancel, thus driving the estimated rate even
> higher. If any of the DYS310 test results are included in the
> "in-house" figure, it is irrevocably tainted. Published results would
> be expected to provide details like which loci are included.
>
> Note: Allan mentioned the BYU world-wide research project involving
> 4-generation pedigrees and a target of 100,000 blood samples. None
> of that project is relevant to determining the mutation rate, since
> they are NOT going after coordinated sampling from closely related
> individuals and NOT preserving names anyhow.
>
> John Chandler
>
> ==============================
> To join Ancestry.com and access our 1.2 billion online genealogy records, go to:
> http://www.ancestry.com/rd/redir.asp?targetid=571&sourceid=1237

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