Tools & Techniques

Finding matches

WikiTree: Find any person of surname x where someone within 8 degrees of separation has indicated they have taken an atDNA test (substitute your SURNAME of choice – caps not necessary):

Ancestry ICW

A network technique documented by Shelly Crawford to show which of your matches connect to whom amongst your up to fourth cousin matches.
This technique utilizes the DNAGedCom client (small sub required) downloads of your ancestry match list and ICW files, and  the basic template from NodeXL (needs Excel 2007+and Windows)
Really helps target the messages to potential matches by showing their connections, and great for navigating between the connected ones.

My post about this – which has already found me a tested “cousin” on a branch of the tree I’ve long been trying to prove the fate of, and given me what seems to be a higher response rate to Ancestry messages.

Shared cMs

The stats from Blaine Bettinger’s survey of actual shared DNA between known cousins

The interactive filter of the above for the amount shared you enter:


Behold Genealogy: Double Match Triangulator
I particularly like his clear definition/distinction between

  • Double match
  • Triangulation
  • Full triangulation

See also TheLegalGenealogist’s blogpost about this new tool (Nov 2016).


  • Free tools
    Try the One to Many report for selected people and use the 3D chromosome browser option to see who all matches whom all else of your selection on which segment
  • Tier one tools (subscription)
    Use DNAGedcom’s instructions for the GEDMatch Matching Segment Search/Triangulation downloads to import the data for a kit from GEDmatch into DNAGedcom for use in the latter’s Autosomal DNA Segment Analyzer.
    Try the new (Nov 2016) Triangulation Groups which Jim Bartlett explained on the Rootsweb DNA list as:
    Think the way it works is like Tree branches: You are the trunk – everyone listed is a Match with you. Then some closer relatives are listed taking off from the trunk; then some smaller branches – taking off from the closer relatives (not the trunk) which form Triangulated Groups. Jim –
Blog posts:

Visual Phasing:

Tests or transfers:

It is recommended that you “fish in many ponds” to milk your DNA tests for as much as you can wring out of them.

Two of the DNA testing companies, and GEDMatch of course, currently (Jul 2017) accept transfers of your raw DNA file.

But (there’s always a but!) that does mean that you are not necessarily comparing like to like and have to bear in mind the differences when evaluating where it is best for you to re-test at another company and when to transfer.

My current conclusion is that if you have tested on Ancestry after they changed to their current chip (mid May 2016), it is marginally better to re-test at FamilyTreeDNA (their FamilyFinder test) than to transfer your Ancestry file to there.

Those having problems converting a newer Ancestry file into FTDNA should explore this tool:

Matches on MyHeritage that look promising need to be checked to learn if they tested directly at MyHeritage or transferred into there – and convinced to upload to GEDMatch anyway for further details.

As at now (Oct 2017) 23andme kits from ?May 2017? are not compatible with the current GEDMatch but can be uploaded to Genesis Beta – with the added advantage there that there they are compatible with LivingDNA tests uploaded to the Beta as well.

X Chr

Roberta Estes DNA-explained: X Marks the Spot
and the follow up: That Unruly X – Chromosome that is
Kitty Cooper: What does shared X DNA really mean