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Archiver > ABERDEEN > 2008-01 > 1201525772


From: Louise Park <>
Subject: [ABERDEEN] Genetics 101 for genealogy
Date: Mon, 28 Jan 2008 13:09:32 +0000
References: <2dff56a0801271054v5fcbf0e0y17969d4991fc82d0@mail.gmail.com><170c01c86118$26a424a0$0200a8c0@dell8400> <005101c86191$19e5c560$3601a8c0@oemcomputer><006001c8619f$898ccea0$0200a8c0@dell8400>
In-Reply-To: <006001c8619f$898ccea0$0200a8c0@dell8400>


I think perhaps we need to explain more simply what can be done with DNA
testing.

What you are calling maternal DNA - which is tested in tracing the
maternal line - is mitochondrial DNA. For those without an in-depth
knowledge of biology, these mitochondria are a structure within almost
all our cells. The DNA in mitochondria ONLY comes from your own mother
(that applies whether you are male or female) because mitochondria are
not present in sperm cells, so the father cannot transmit this type of DNA.

The Paternal line is traced using y-DNA - this is the DNA that is
present in Y chromosomes, which only genetic males and a very few women
with XXY (or similar chromosomal abnormalities) have.

These techniques are very different from the type of screening that is
done in say paternity tests as seen on the likes of Jeremy Kyle's show -
these tests screen the genomic DNA, of which 50% comes from the mother,
and 50% from the father. These are pretty well useless in genealogy
unless you are trying to prove whether your have the same father as a
sibling.

So to answer Janet's question - no, testing of your mitochondrial DNA
would not reveal anything of your mother's putative father's DNA.
However, if there was a confirmed child of your mother's putative
father, they and your mother's DNA (if both were still alive) could be
tested to see whether they had the same father using genomic DNA.

I shouldn't think that swabs would "go off" between the USA and Oxford -
after all, they can do DNA testing of samples that are decades old (and
more)!

Hope that clarifies.

Louise

Janet wrote:

>What I was wondering - a wild thought - if I underwent the maternal DNA whether it would indicate anything of my Mother's putative father's DNA. Or, in a more simplified way, does a female DNA contain anything of a paternal male component. Complicated isn't it.
>
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