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Archiver > GENEALOGY-DNA > 2006-05 > 1147121033


From: "Ken Nordtvedt" <>
Subject: Re: [DNA] Brown eyes
Date: Mon, 8 May 2006 14:43:53 -0600
References: <215.1680f28d.3190f1f0@aol.com>


I have been trying on this list for 1 1/2 years to flush out the numbers of
how frequently the "dominant brown eye gene" does not work, and all I get in
return is endless talk about complexity, but no numbers or reference to data
on "failure rate" of the rule. From observation I believe the rule works
almost all the time. That's all that is needed for population studies ---
at least my particular application; my purpose is not family genealogy.
Dissect what is in your quote of Frudakis and it is not particularly
pertinent until it converts into a quantified (big, medium, small?)
disturbance of the empirical rule of the dominant brown gene model --- his
words were all about associations of SNP sites with gene sites, etc.

So now I find one site which quotes some numbers --- it suggests the rule
fails about 1 percent of the time. If that estimate is bogus, maybe it will
flush out the true rate from someone who has seen the numbers or reference
to the numbers?

I am not interested in prolonging these word games; there would be a
practical application I am interested in in population studies (and
potentially rate of selection against the brown gene) if the data of brown
eye percentages by regional populations (much like the existing blood group
data) exists, but so far that has eluded searches and perhaps does not
exist.

Ken


----- Original Message -----
From: <>
To: <>
Sent: Monday, May 08, 2006 1:11 PM
Subject: Re: [DNA] Brown eyes


> In a message dated 05/08/06 11:27:43 AM Pacific Daylight Time,
> writes:
>
>> Except for the brown dominance gene. It seems to obey the behavior rules
>> of
>> a single dominant gene except in less than 1 percent of the cases there
>> is
>> an epistatic gene which suppresses expression of the brown gene, so a
>> person
>>
>> in that infrequent case would show blue eyes even though having a brown
>> gene.
>
> I found the website you quoted in another message -- I'm a bit surprised a
> die-hard skeptic like you is so willing to accept that sort of hearsay
> evidence
> :)
>
> I'd be discouraged about using brown eye color phenotype as a clue to
> common
> ancestry, given statements like this from the second Frudakis article in
> my
> prior message:
>
> "These analyses resulted in the identification of 61 SNPs in 16
> genes/chromosomal regions associated with iris colors on one level or
> another."
>
> "...Other genes such as AIM, OCA2, and TYRP1 harbored haplotypes
> positively
> associated with brown but negatively associated with blue color..."
>
> "Overall, the diversity of haplotypes associated with brown irises was
> similar to that of haplotypes associated with blue irises."
>
> Ann Turner
>
>
> ==============================
> Search the US Census Collection. Over 140 million records added in the
> last 12 months. Largest online collection in the world. Learn more:
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>
>


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