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Archiver > GENEALOGY-DNA > 2009-11 > 1258896657


From: "Mike" <>
Subject: [DNA] Autosomal Matches
Date: Sun, 22 Nov 2009 08:30:57 -0500
References: <EEE2A302988449359D82FC60F1E9D01B@whit>


I would appreciate comments from the list members regarding a Partial Genome matching situation that exists between myself and another individual at 23andMe via their Relative finder - we share a small DNA segment on Chr 2, the son and I, but not the mother.

The son was puzzled by this and was wondering how he could match me; yet not his mother. After some though, I wrote the following to him as a possible explanation, and my question to the list is "were my words reasonably accurate?" If not, what might explain the situation?

"After re-reading your comment a couple of thoughts came to mind. The first is that our shared DNA is autosomal and not X, Y, or mitochondrial, which means (I think) that the relationship might also exist from your father's ancestry, regardless of the fact that we have differing haplogroups (based on Y-DNA & mtDNA).

The second is that a second person who shares DNA with me (Chr 21) is the mother of the son who manages their family's information on 23andMe. Yet I share NO DNA with the son, or his 2 other family members.

So it may very well be possible that our cousin relationship exists back as far as a 4th GGrandparent.

Perhaps this example shows the utility of 23andME's autosomal testing in that it can point-out relationships beyond the pure paternal & maternal lines of Y-DNA & mtDNA even though they may exist beyond the present knowledge of our personal ancestry."

Thank you, Mike Z

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