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techteach;38424 wrote:
The third shot is the segment tool. As you can see, I don’t have a lot of segments identified. The problem is, you have to make sure that you know the genealogy of your matches. I was able to identify some Sinkey from a match who has only my Sinkeys as well as a Ralston-only match (but in this case, there was a share back to my Blackfoot, so I am not sure where that is coming from. I have not had matches that have helped me break that Blackfoot deadend.). I cannot afford all the DNA testing that some people do to accomplish things like finding biological parents. And I don’t fully understand this program when it asks you to identify maternal and paternal lines, so I hope I guessed right how to do it.
There is a Facebook page you can post to for help.
Cindy
This is a dumb question, but what is the purpose of chromosome mapping? I have found a couple common ancestors and colored in a couple segments, but I don’t understand the value in doing so.
GGM_Robbins;38439 wrote: This is a dumb question, but what is the purpose of chromosome mapping? I have found a couple common ancestors and colored in a couple segments, but I don’t understand the value in doing so.
With chromosome mapping you can identify segments of DNA by ancestry or admixture. For instance if you know a certain segment is shared by a relative on your maternal side you can narrow down the possible sources of common ancestry. With admixture it maps the segments by suspected ethnic group. So you can narrow down possible ethnicity of a segment.
If someone had DNA samples from themselves and all four of their grandparents they could map their entire DNA into four groups. Then at that point with any cousin match, you would know right away which grandparent you are related to that cousin through.
MarcSnelling;38444 wrote: With chromosome mapping you can identify segments of DNA by ancestry or admixture. For instance if you know a certain segment is shared by a relative on your maternal side you can narrow down the possible sources of common ancestry. With admixture it maps the segments by suspected ethnic group. So you can narrow down possible ethnicity of a segment.
If someone had DNA samples from themselves and all four of their grandparents they could map their entire DNA into four groups. Then at that point with any cousin match, you would know right away which grandparent you are related to that cousin through.
OK, that makes sense, Marc. If you don’t have samples from your four grandparents is the best alternative triangulation?
Ancestry just introduced tools to help with triangulation or actually do the triangulation if I understand it. There are 2 new tools:
1. If you tested a parent, you can sort which matches come from that parent.
2. They also added a tool where you can see matches that you share with someone.
These are helpful for those long lists of people who test their DNA without having a tree. I was hoping for help with private trees too, but no such luck. It is going to save me a lot of time trying to sort by hand who matches Dad by looking at who matches Mom.
I hope it will also help me identify my Blackfoot DNA. I have found specific Ralston DNA locations that I inherited through a relative who uploaded to Gedmatch, and then I played with their results in Genome Mate. However, she shares my Blackfoot ancestor too, so it is not possible using her results to differentiate the Ralston DNA from the McLane (my Blackfoot ancestor) DNA. Now, if I can find someone who has Ralston only and get them to upload to Gedmatch, I can pinpoint which segments come from Ralston and which from McLane.
Techteach
MarcSnelling;38400 wrote:
Other connections from people at SaponiTown; are Brenda Collins Dillon also shared common Miller ancestors from this line, Rachel Payne whose GEDMATCH was shared here. Dave Parrish also shares this segment, along with a number of matches names Cousin, Montgomery, Brown, Hall, Stevenson, Androy, Willy, Brown, Allen, Hicks, Speck, Henningfield, and Newdigate.
I was wondering if Saponitown has any centralized inventory of its members’ Gedmatch IDs. If not, it might be useful to compile one. This thread came to my attention when I searched on “Gedmatch,” because you (Marc Snelling) just listed several Gedmatch numbers from your family on the “Tracking down the Green family” thread.
I don’t know if I’ve had occasion to mention mine, it’s M195517. One of my best matches is Rachel Payne, A483312 — a little bit on nearly every chromosome (one must lower the cM threshold to see them), and one long segment of 43 cM on chr 12. She also shares apparent Native American ancestry with me, per chromosome painting. I have tried a couple of times to contact her, via the email address listed at Gedmatch, but got no response.
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