Third party DNA tools

By Kitty Munson Cooper Blogging at

slides at

Why use a 3rd Party DNA tool?

  • Look at how your DNA relatives relate to each other visually: Clustering

  • Compare to relatives who tested elsewhere (GEDmatch)

  • Other specialized tools: find haplogroup, check consanguinity

Relationship Calculators

The daughter of my cousin CIaire shares more DNA with me than any other first cousin once removed

619 cM

Here are Ancestry's estimates on how we are related

My favorite tool is the online calculator at

Enter the cM and see probable relationships 


But there is another Calculator which adds in segment sizes by including the number of segments -

You might try using the "What Are The Odds" tool at DNApainter to check your relationship theory - 

If you can make a GEDCOM of the descendants of the common ancestors, you can upload that to WATO … 

An unknown father case named B had a 779 cM match to a person  some 35 years younger and also a 324 cM match to the daughter of the match

normally that might be enough if the match responds and helps but no such luck

So we checked the possibilities at my favorite online calculator

To combine the probabilities of all the DNA matches to descendants of Caleb Browning b 1832 we made this WATO tree

N.B. The father of the good match is the same age as our B

There is a facebook group as well as an ftDNA project for our terminal SNP L-238

what does the DNA-SCI calculator tell us?

Now the daughter of the best match - expected half 2G niece

Why is GEDmatch the best place to compare your kit to DNA tests from Ancestry or from other testing companies?

- MyHeritage does not show the X nor can you           compare your matches to each other

- Family Tree DNA does not show comparisons of        third parties to each other nor triangulations

- Neither shows fully identical regions (FIRs)

- and there are many segment level tools at GEDmatch

Law Enforcement and Genetic Genealogy - GEDmatch

Clustering is a great tool for visualing how DNA cousins are related

Clustering can be a quick shortcut to finding the common ancestors with a cousin. The idea is to display your matches who match each other in an easy to understand visual format

You can sign up to cluster at or you can use the clustering tools from or GEDmatch or MyHeritage or DNA2tree

The result might look like this, each colored box is expected to consist of matches descended from one set of your great grandparents

On some versions of clustering, all the names are clickable to the match (others have a list below)

Note that the boxes are not the perfect 4 - probably because the low end was selected as 30 cM, try 60cM

Sample of clustering at GEDmatch

MyHeritage includes a cluster tool from Genetic Affairs

I recently found a 3rd cousin, Melissa ... Her cluster includes many Munsons so that is where she must belong

In the lists of people for each cluster your notes are included and everything is clickable

Genetic Affairs can do auto-clustering from FamilyTreeDNA and 23andme

 Genetic Affairs also has a tree building feature.



Sadly for adoptees, has disallowed this

DNA2tree is only on iPhones and iPads via a paid subscription but it is a real game changer for unknown parentage searches

It automates finding common ancestors at Ancestry

DNA2tree also has clustering

DNAgedcom has many tools, focused on helping adoptees

DNAgedcom has a paid client that will collect your match data from most web sites

These are the names of the original Spanish settlers of New Mexico

The numbers of trees each ancestor appears in scream out ENDOGAMY

GWorks from DNAgedcom can make a database of common ancestors from your matches

You can create kits for deceased relatives from existing kits at Borland

The idea of the genetic family site is a place to consolidate your data from the many test sites

You can determine the likely Y haplogroup from a male Ancestry DNA kit with the Morley Tool

How to do that is explained here on my blog


Third Party DNA Tools - 2023

By Kitty Cooper

Third Party DNA Tools - 2023

Exploring many 3rd party DNA tools: relationship calculators, clustering. WATO

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