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 home page for GEDmatch

Click the learn more to see a youtube video from Andrew Lee of FHF which explains how to register for a user id and upload your DNA kit

Scroll down that home page and see this

https://www.youtube.com/watch?v=id7JJ1NoTNk&feature=youtu.be

Or click the link above to get to that video

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 !

My Home page at GEDmatch 

When you log in your information and uploaded resources are listed on the left side of the page below the day's messages and the welcome

we call this the Dashboard Page

The bottom of your Dashboard Page 

notice the CONTACT US button!

The free tools are listed in a panel on the right of the Dashboard

If you have just uploaded a kit there are a few things you can do while you wait for it to be ready to use (aka "tokenized")

See these slides of mine for how to use the admix tools: https://slides.com/kittycooper/gedmatch

You can play with the admixture tools, many have not been updated in years but they are still fun and different from your testing company

You can run the

DNA File Diagnostic Utility 

you want to see a

Status: Good

I am often asked about  slimming

for the purpose of quick comparisons the heterozygous SNPs are removed because with one of each base, those SNPs match everyone

Next check use the "Are your parents related" tool as this can make it harder to figure out new relatives

Unless you are from an endogamous population or know your parents are cousins this will likely be negative

sample negative result

sample negative result

blog.kittycooper.com/2018/07/when-the-dna-says-your-parents-are-related/

At the bottom right of your dashboard are the tools for family trees stored as GEDCOMs

I recommend uploading a privatized GEDCOM with about 10 generations of ancestors for your kit

blog.kittycooper.com/2015/04/using-the-gedcom-capabilites-at-gedmatch-com/

Since a GEDCOM is a text file, you can edit it in a plain text editor like the notepad on a PC

I recommend changing the first names of anyone living to just LIVING

and removing birth month and day leaving the birth year

GEDCOM + DNA matches

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

You need to know the kit numbers of your known relatives (easier once you can do a one to many)

I recommend setting up a group for each great grandparent line using the same colors you used at Ancestry or on your Leeds Chart 

Click on the green 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 via the Manually Add Kits

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

Notice that the kit number is colored with its tag group

https://blog.kittycooper.com/2017/04/using-gedmatch-tag-groups/

If the kit is connected to a GEDCOM or to a tree at WIKItree that shows here

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 clicked on her kit number to look at her one to many

I could tell immediately from the tag group colors 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 new Munson cousin

Some of the  FREE tools that I find invaluable are highlighted

Checking my new cousin in the relationship probability tool by entering the shared cM

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. 

https://segmentology.org/2015/05/07/what-is-a-segment/

https://blog.kittycooper.com/2014/10/when-is-a-dna-segment-match-a-real-match-ibd-or-ibs-or-ibc/

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

http://blog.kittycooper.com/2014/01/what-does-shared-x-dna-really-mean/

New exciting tools typically come to Tier 1

The first thing to do is make a combined kit if you have tested at multiple companies

Visual comparison of my 23andme kit to my Ancestry kit

Tier 1 One to Many

You can check boxes next to multiple kits and then use the visulize button to use the multikit analysis tools

MULTI-KIT ANALYSIS (Tier 1)

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

CLUSTERING

AUTO Kinship

The result has to be downloaded

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?

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

https://www.youtube.com/watch?v=AjA59BG_cF4

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 

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 slides.com/kittycooper

my blog is at blog.kittycooper.com/