Wednesday, July 1, 2020

Where Are the "Holes" In My Pedigree Chart? Can DNA Help? - Post 1

While wading through my Genetic Affairs AutoCluster results for AncestryDNA (seMy Last AncestryDNA AutoCluster AutoTree Analysis From Genetic Affairs - Post 1), I noted that I have many DNA match clusters that don't have a known common ancestor, based on my Notes for each DNA Match.  For instance cluster #1 has 26 entries, but no known common ancestor.  I'm pretty sure that the common ancestor for that cluster is on my father's Seaver side of the family, but none of those matches has an Ancestry Member Tree that includes one of my Seaver line ancestors back up to the 5th great-grandparents.

I have about 400 AncestryDNA ThruLines that define Common Ancestors for me based on my tree, DNA match trees, and the Ancestry Big Tree.  These are very helpful, but are not always accurate (my estimate is that about 5% of my ThruLines are incorrect).  

There are more Common Ancestors identified with ThruLines than by Genetic Affairs because of the methodology used by each analysis (Genetic Affairs uses only my tree and a DNA Match's tree, not the Ancestry Big Tree).

How can I figure out who might be the Common Ancestor for more of my DNA Matches, especially in clusters?  The first step should be to define what I think I know and what I don't know about my ancestry.  Here is a 7-generation chart from the FamilySearch Family Tree (out to 4th great-grandparents).  I wish I could make an 8-generation chart to get to 5th great-grandparents!

My unknown ancestors on this chart are:

*  4th great-grandparents, parents of John Richman (1789-1867).

*  4th great-grandparents, parents of Ann Marshman (1784-1856).  The chart shows parents that I think are incorrect.

*  4th great-grandparents, parents of John Rich (1790-1868).  The chart shows parents that I think are incorrect.

*  4th great-grandmother, mother of Sarah Feather and wife of Cornelius Feather.  The chart above calls her Mrs. Cornelius Feather.

*  3rd great-grandparent, a parent of Devier J. Lamphier Smith (1839-1894).  Devier was adopted as an infant, and I'm pretty sure one set of his grandparents are Isaac and Rosanna (Laun) Lanfear (based on DNA matches), but the other parent (male? female?) is a mystery.

*  4th great-grandparents, parents of William Knapp (1775-1856).  Ancestry offers potential ancestors that I am sure are incorrect.

*  4th great-grandparents, parents of Sarah Fletcher (1802-1850).  

I have other "holes" in the 5th great-grandparents not shown on the chart above that may be the Common Ancestors of some of the Genetic Affairs clusters.  

My next step in this analysis process is to identify my AncestryDNA Common Ancestors on the fan chart to see which of my known ancestors don't have any matches, and which clusters might account for one or more of my "holes" in my fan chart.


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1 comment:

Diane Gould Hall said...

That’s such an impressive chart Randy. You’d be sad for me, if you saw mine. But, I’ll keep working and maybe get there one day. Good job!