Today there is an ever increasing interest for those working in genealogy to look for new ways to apply genetics to traditional genealogy. I am working on a project for the Morrison-Q-DF41 Group to confirm connections to specific ancestors through matches of Autosomal DNA to common descendants. Another goal is to “map our chromosomes” and specifically identify the Morrison chromosomes. A good thing about Autosomal DNA is that it is inherited by both males and females, so anyone can participate in this project.
The more people who participate in the Autosomal DNA test (called the Family Finder test at Family Tree DNA (FTDNA), the better conclusive results we will have from this analysis. It would be especially helpful to have those who are closely related to take the test, i.e. father/son, brother/sister, uncle/nephew or first cousins. Then we need you to load your raw DNA data file to GEDmatch.com so I can do a detailed comparative analysis of the various DNAs. If you have already done an Autosomal DNA test (Family Finder, Ancestry.com or 23&Me), we need you to load your raw DNA data file to GEDmatch.com and notify me of your kit number. If you need instructions on how to upload your raw DNA to GEDmatch.com, read the instructions at the following pages:
GEDmatch.com is a free, volunteer-run website that allows persons who have tested their Autosomal DNA at different testing companies to load their raw DNA data file. Then users can compare their DNA to everyone else in the database or to a specific individual in the database. Numerous admixture analyses tools are available at GEDmatch, allowing users to triangulate their matches.
Triangulation is the only way you can prove that you do indeed share a common ancestor with someone not previously identified as family.
To confirm that you share a common ancestor with someone, you need to either:
- Be a close relative – meaning you tested your mother and/or father and you match as expected. Or, you tested another known relative, like a first cousin, for example, and you also match as expected. These known relationships and matches become important in confirming or eliminating other matches and in what is called mapping your chromosomes to specific ancestors.
- Be a triangulated match to at least two others who share the same distant ancestor. This happens when you match other people whose tree indicates that you share a common ancestor, but they are not previously known to you as family.
To prove that you share a common ancestor with another individual, the DNA of three proven descendants of that common ancestor must match at the same location on segments of 7 cMs in length or larger. If you are a fourth person and match all three of those persons on the same location, then you also share that same common ancestor. This is the same process used by adoptee firms when searching for the identity of a parent.
Triangulation itself is a two-step process followed by a third step of mapping your own DNA so that you know where various segments came from. The first two triangulation steps are discovering that you match other people on a common segment(s) and then determining if the matches also match each other on those same segments.
We hope you will consider joining the other Morrison-Q Autosomal DNA Project Members who are participating in the Morrison-Q Autosomal DNA Project. If you have any questions about the project or would like to join, please feel free to contact me at email@example.com.
RENE WILLIAMS BRYSON