Re: exact match for 37 markers
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In reply to:
exact match for 37 markers
Marjorie Barron 7/02/09
It is possible, but but has a low probablility. You can see this by running McDonald's calculator at:
http://dna-project.clan-donald-usa.org/tmrca.htmhttp://dna-project.clan-donald-usa.org/tmrca.htm
Select cumulative probability and list. Note that he uses transmission events, which must be divided by 2 to get generations. You can see that the cumulative probability approaches 1 very slowly at the end.
I would search the the surname boards with the other surname to see if anyone has run across an NPE. Until you can pin down the generation and location of an NPE, doing new research in unmanageable.
The next thing to do is to determine the Ancestral haplotypes for each family.See:
http://genforum.genealogy.com/dna/messages/1405.htmlhttp://genforum.genealogy.com/dna/messages/1405.html
http://www.kerchner.com/triangulation.htmhttp://www.kerchner.com/triangulation.htm
This will determine whether a possible NPE occurred prior to the progenitor. If so, the testing will eliminate fruitless research into later connections.