Advanced Tools at GEDmatch: Using Segment Data and more
All my slides are always online at
The new home page has much help for new users plus messages about what's new on GEDmatch
GEDmatch is still the best place to compare your kit to DNA tests from other companies
example of the one to many comparison
Why is GEDmatch is still the best place to compare your kit to DNA tests from Ancestry or relatives tested at different companies?
- MyHeritage does not show the X
- Family Tree DNA does not show comparisons of third parties to each other nor triangulations
- Neither shows fully identical regions (FIRs)
- and there are way more segment level tools at GEDmatch
Some of the FREE tools that I find invaluable are highlighted
Be sure to always check that your newly uploaded kit has uploaded correctly
When uploading a new kit be sure to check if the parents are related, if they are this can make it harder to figure things out
There is a now a relationship calculator
The free version of the One to Many shows the testing company and how many SNPs are in common between the kits
The column headings are explained in this post
Close up: note the testing company and how many SNPs are in common between the kits and mitoYDNA has been linked to a haplogroup
Click the largest segment under autosomal to get the one to one comparison for that match, same for X
How to get the image only?
Check graphic only on the form
If you and a DNA relative are both tested at Ancestry, you can upload to GEDmatch to see the actual segment data
Viewed as an image, the HIRs (half identical regions) show as blue bars and the FIRs (fully identical regions) show as green bars
Why is this useful? Well to have fully identical regions with a relative you need to be related on both your mother's and father's sides. Full siblings, 3/4 siblings, double first cousins
See explanation at blog.kittycooper.com/2019/10/why-dont-we-share-more-dna-with-a-sibling/
3/4 siblings HIRs + FIRs = theoretically about 2500
example known 3/4 siblings: 2267.7 + 533.8 = 2801.5
Most comparisons will have only blue bars and no green bars of any significant length
Another option on the one to one form is to show only the FIRs? doubly related people like full siblings, 3/4 sibs, double first cousins will all have these
Normal one-to-one image chr 1-8
For why only FIRs are useful see blog.kittycooper.com/2019/10/why-dont-we-share-more-dna-with-a-sibling/
At the bottom of the image comparison are the numbers
The X is often important for figuring out relationships.
Sisters who share a Dad will share a full X, see
Two HALF sisters
Two full sisters
The X chromosome is a separate comparison
Note that here we are getting both numbers and image
Be sure to check the Prevent Hard Breaks on the X form
Tag groups make the one to many more useful, see
To see your tag groups check either One or All in Tag Groups
The one to many with tag groups for a close cousin tells me quickly how they are related
People who match both kits, or 1 of 2 kits
Some of the Tier 1 (so PAID) tools that I find invaluable are highlighted
Combine multiple kits into 1 superkit
you can make a kit which combines all your test results from different companies
More about this tool at
Find common ancestors in the trees of your DNA matches - here are my results
Click on PTH to see the below, the 3G or whatever G shows the descent for that one person from the common ancestor
In Tier 1 you can check the checkboxes from the one to many or kits that match 2 kits and then click on visualiztion oprions to get to the MULTI KIT ANALYSIS
You can do a matching segment search for just the selected kits
Even better is a triangulation for just the selected kits
My Compact Chromosome Browser
The 3D chromosome browser includes multiple matrices, autosomal. X, and number of segments
Tier 1 members have a more accurate One to One for checking on the validity of small segments
A normal one to one
My and my double 3rd cousin, shared Jewish ancestral couple
The Q matching One to One
Q pile ups: My aunt and my new 3rd cousin
SNP density: My other aunt and my new 3rd cousin
Recently a Norwegian DNA match to Dad with a deep family tree found that he is my 12th cousin twice removed
His single segment match to my Dad and my brother is in a pile up area with about 100 or so matches on the various sites
Actually GENI figured it out for us.
So now I wonder if those many other matches on this 12cM pile up area are also descended from this ancestor
Could I investigate using thegranularity on
Segment Searches (Tier 1) ?
OOPs, I see cousins on both Dad's paternal and maternal side. How might I ensure that those overlapping segments triangulate?
This way found 64 segments. My brother has this same pile up ....
A phased kit of the DNA my brother got from my father can be used!
Much better, only 54 and only his maternal cousins now
The GEDcom tools were the first apps on GEDmatch before autosomal DNA, they are still useful
Can software figure out the family tree from the shared DNA?
The result has to be downloaded
After you download it and unzip it click on the folder Autokinship then on the HTML file autokinship to see a long page in your browser: first the clusters
My auto kinship clusters
one endogamous population grandparent, and another missing from the testing community
Since so many of my MUNSON cousins are tested ... what would autokinship came up with for that cluster 2 green box?
Lauritz + Josephine Monsen
Pretty accurate. I have identified which child of my great great grandparents each match is descended from. Only the last one is not, he is actually descended from a sister of Josephine's
A closer look at my cousins with the one generational correction
Next is a matrix of how many cM they each share with each other
And finally there is a list of shared segments that met your criteria
Tim Janzen did a great Rootstech talk about these new features at
Shall we look at the auto tree for my endogamous cluster?
Here are the few trees created for cluster1 - the problem is not enough kits have linked trees on GEDmatch
Gugenheimer and Thannhauser are known ancestral lines, not Shadur
help in unknown parentage cases?
Advanced Tools at GEDmatch: Using Segment Data and more
By Kitty Cooper