GENEALOGY-DNA-L ArchivesArchiver > GENEALOGY-DNA > 2010-03 > 1269808698
From: John Carr <>
Subject: Re: [DNA] 23andme cousin results
Date: Sun, 28 Mar 2010 13:42:57 -0700
I see what you mean, so the anticipated % comparison between a child and the parent or two siblings is really ~85%, not the 50% that is often quoted. The 50% refers to the entire genome, not the anticipated match within the selected SNPs used to make the comparison.
On Mar 28, 2010, at 10:42 AM, Vincent Vizachero wrote:
> Actually, the explanation for this is that two parents have genomes
> that are something more than 0% identical to each other. In fact,
> even complete strangers are about 65% to 75% identical for the SNPs
> commonly tested.
> So, if roughly 50% of my DNA comes from my father (that part must
> match 100%) and 50% comes from my mother (and my mother is, say, a 70%
> match to my dad given that they are genetic "strangers") then I will
> match ((.5*100%)+(.5*70%))= 85% with my father.
> On Mar 28, 2010, at 1:31 PM, John Carr wrote:
>> Perhaps this male recombination bias David mentioned explains why
>> parent to child shared results and sibling shared results are
>> consistently around 84% rather than the 50% that is offered as the
>> expected shared result.
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|Re: [DNA] 23andme cousin results by John Carr <>|