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

The DNA File Diagnostic Utility output

 

you want to see a

Status: Good

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

https://blog.kittycooper.com/2016/06/gedmatch-tools-2016/

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

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