Using the tools at GEDmatch:
the Basics for Finding Relatives and more
By Kitty Cooper, blogging at blog.kittycooper.com -
slides always at slides.com/kittycooper
This is the new home page coming soon!
This is the current home page
not pretty, but clear, either
log in
or
register (free)
This youtube video from Andrew explains how to register for a username and upload your DNA kit
and the second part of the new home page even sends you to that video to learn more
GEDmatch was founded to let you compare GEDCOMs and autosomal DNA results from different companies with powerful analysis tools
A problem is that the various DNA testing companies test different SNP sets which are not the same although there is much overlapping
So GEDmatch developed a special template for comparing them !
Top of Basic Dashboard Page at GEDmatch
What you see after logging in
Tools listed on right of Dashboard at GEDmatch
New Dashboard Page at GEDmatch
same functionality and layout just prettier
New Dashboard Page below the fold at GEDmatch
notice the help button!
Use the information box to learn more
Notice in the new site all the help is bundled into the "How to Use GEDmatch"
New Site
Current Site
While you wait for your kit to "tokenize" so you can use the ONE TO MANY tool
You can run these starred tools
See these slides of mine for how to use the admix tools: https://slides.com/kittycooper/gedmatch
Home Page at GEDmatch
before any uploads
Next Upload a GEDCOM of your Family Tree
Please upload a privatized GEDCOM with about 10 generations of ancestors for your kit
GEDCOM + DNA matches
There can be a lot of information on the first page, the individual, in a gedcom
But typically we just click to see the pedigree
Top half of my Aunt's pedigree, the clickable little tree shows where a match to another GEDCOM has been confirmed
2 GEDCOMs comparison
The next thing to do is set up your tag groups
I recommend setting up a group for each great grandparent line using the same colors you used at Ancestry or on your Leeds Chart
Also perhaps a group for close family and for localities see
https://blog.kittycooper.com/2017/03/gedmatch-tag-groups-plus-new-one-to-many/
Click on the button Display/Edit tag group to get to this page
Once you have created a tag group. add the kit numbers of your known relatives at GEDmatch
Some of my tag groups
Once you have a GEDCOM uploaded and tag groups set up, it is time to use the most important tool for finding relatives: the One-To-Many
The basic one-to-many shows the kits that match the kit number you give it with the overlap indicating how many SNPs are in the comparison, red means too few, and it shades down from there
[email column has been removed for this slide]
You may want to use 10cM or even 20cM for the minimum largest autosomal segment to make a faster and shorter list
Beta One-to-Many - includes tag groups (check one or all) https://blog.kittycooper.com/2017/04/using-gedmatch-tag-groups/
This old post explains the column headings like Gen
Every column is sortable, I often sort by largest segment, see
https://blog.kittycooper.com/2015/08/size-matters-for-matching-dna-segments/
Recently I had a close match with a name I did not recognize, so I looked at her one to many
I could tell immediately from the tag groups of her matches that she was a Munson
If tag groups don't solve where a match is related try
The ICW function:
"People who match
one or both kits"
Comparing my Dad and my 2nd cousin with threshold 8cM
Be sure to run this tool - AYPR
Multiply the shared cMs by 4 to get the approximate amount the parents share - this person's parents are known 5th cousins
SEGMENT DATA
A matching segment of DNA is where a long run of SNPs are the same in two different kits. The problem is that the testing process cannot tell which side they are from. Thus the match can even be from a mix of the two sides, maternal and paternal.
One to one with numbers and graphics (partial page)
My double third AJ cousin
One to one without the graphics, position only
My double third AJ cousin
One to one without the graphics, position only but NO HARD BREAKS
My double third AJ cousin
One to one just graphics with my double third AJ cousin
Full siblings always have some fully identical regions (FIRs) - where both strands of DNA got the same SNPs from their parents - those are the green bars
this is the graphic only, one-to-one, for my brother and myself
FIR only version of my comparison of my brother and my Ancestry kits
One to one on the X chromosome with my double third AJ cousin
If you have tested at more than one company, since they may have tested some different SNPs, best to upload both and combine them into a super kit (then mark the base kits research) see
https://blog.kittycooper.com/2019/04/make-a-combined-dna-kit-for-yourself/
Visual comparison of my 23andme kit to my Ancestry kit
CLUSTERING
MULTI-KIT ANALYSIS (Tier 1)
Multiple Kit Analysis is only on the Tier 1 menu - Tier 1 members can also get there by checking the boxes in the one to many tool or in the kits that match two kits tool and clicking Visualization Options
The multiple kit selection form lets you add more kits by typing or selecting from your kits in a drop down or even using your tag groups
So many options for Multi Kit Analysis
You can do a matching segment search for just the selected kits
You can do a triangulation for just the selected kits
To understand triangulation try this article at the ISOGG wiki https://isogg.org/wiki/Triangulation
Form to do a triangulation, enter your kit number, the defaults are fine
Sorted by Chromosome and Position with Graph
Sorted by Kit Number has more information and can be resorted in a spreadsheet
My Chromosome Browser at Genesis
Phasing
- If you have at least one parent tested then you can separate what you got from each parent
- If the maternal or paternal phase can be determined the values will be assigned else the original unphased values will be kept
LAZARUS lets you create a kit for comparisons for a person who cannot be tested from their close relatives
All my presentation slides are online at https://slides.com/kittycooper
GEDmatch Basics 2021 - FHF Winter of DNA
By Kitty Cooper
GEDmatch Basics 2021 - FHF Winter of DNA
Using the tools at GEDmatch, the Basics for Finding Relatives and more: Presentation by Kitty Cooper http://blog.kittycooper.com
