GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2005-05 > 1115054680


From: "" <>
Subject: RE: [DNA] Need help interpreting close results
Date: Mon, 2 May 2005 13:24:40 -0400


Tracey,

The situation you describe permits differing interpretations. The right
interpretation is going to depend on estabishing the ancestral and mutated
values the two markers where variation is observed.

For example: If you assume that the ancestral value at 459b is 10, then
following the general rules of sorting out variations I'd say that 21477
and 20650 share a more recent common ancestor with each other than either
does with 15853. That's because the two of them share a mutated value that
the third man does not. No other shared mutation is seen in this set of
three.

On the other hand, if the ancestral value for 459b is 9, it is possible
(but not certain) that the value 10 in 15853 is a recent mutation.

DYS456 is a semi-fast mutator, which can make it valuable in sorting out
lines in complicated families. In one surname project I follow
(Lovelace/Loveless), DYS456 by itself brought clarity to a confusing set of
family groups and let us organize one branch of the tree very clearly. That
made it easier to see who had to belong to other branches.

Don't worry about mutation rates. If you observe a mutation in a family
study, it's the fact of the mutation in context that you must account for.
You shouldn't care what the odds were against that mutation occurring in
that location at that time.

John Carr's question about the paper trail is a good one. Do you have
reasons to connect these three individuals, or any two of them? If not, can
you at least determine they originally came from the same geographical area?

David Wilson



Original Message:
-----------------
From: Tracey Marcelo
Date: Sun, 1 May 2005 22:36:32 -0500
To:
Subject: [DNA] Need help interpreting close results


Hi,

My cousin is part of a surname study, in which 37 markers were measured.

When comparing close matches among three participants, we got some results
that I would really love some help with interpreting.

The three we are comparing are only one or two markers from each other.

All three had different values for DYS456:
Participant 21477: value 19
Participant 15853: value 18
Participant 20650: value 17

Participants 21477 and 20650 are only one marker off because of this marker.

Participant 15853 is two off from both of the other participants at DYS456
(as described above) and at DYS459b. His value for DYS459b is 10; however,
21477 and 20650 both have 9 as a value for this marker.

What stuck out to me were the markers at which they differ from each other
and by how much.

Do these results indicate anything noteworthy about these lines?
For example, could it indicate something about the mutation rate?
Or could it indicate something about the estimated MRCA of these three
participants?

Thanks,

Tracey




==============================
Search Family and Local Histories for stories about your family and the
areas they lived. Over 85 million names added in the last 12 months.
Learn more: http://www.ancestry.com/s13966/rd.ashx


--------------------------------------------------------------------
mail2web - Check your email from the web at
http://mail2web.com/ .



This thread: