4 key online DNA resources


09 April 2023
To mark DNA Day 2023 - and the 70th anniversary of the discovery of the double helix, Helen Tovey presents four key resources for using DNA in family history.

It’s 70 years since Crick and Watson first published their paper in Nature about the structure of DNA. The double helix had been identified and was beginning to be unlocked.

Seven decades on, DNA is a crucial element of family history research for many of us, allowing us to make contact with distant relatives around the world, and to share our research findings.

Here, Family Tree editor Helen Tovey presents four top DNA resources:

The International Society of Genetic Genealogy (ISOGG) 

An international society. It sounds amazing doesn’t it, and impressive. And it is. And you can join, right now, free. Simply head over to their website.  Established in 2005, ISOGG exists to help promote the use of genetic research into the field of genealogy and to help provide educational information and materials for free use to all. Check out the Wiki – with more than 700 articles; see also glossary, timelines, test comparison tables and more. 

Tracing Your Ancestors Using DNA 

Co-authored by John Cleary, Michelle Leonard, Alasdair F. Macdonald and Iain McDonald, and edited by Graham S. Holton, Tracing Your Ancestors Using DNA: A Guide for Family Historians was published by Pen & Sword in 2019. Available from Pen & Sword.

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The Shared cM Project 

Begun in 2015 by Blaine Bettinger, the project is now on version 4 and has collected information from more than 60,000 people who provide information about the number of centiMorgans they share with a known DNA match. This is the important bit: the project has collected info about the number of cM that people of a specific relationship (e.g. Aunt and Niece, Grandpa and Grandson etc etc) share with each other. The project table created by Blaine Bettinger allows you to see the average number of cM shared between two people of a specific relationship – and it provides the lowest and highest number of shared cM too.  

Try it out for yourself: see here and see also the Shared cM Project Tool here.

Jonny Perl’s DNA Painter site 

In addition to the Shared cM Project Tool, Jonny Perl is the innovative mastermind behind a raft of DNA tools found on his site, dnapainter.com. Such as What Are The Odds? (you suggest a hypothesis, and fill the DNA details you’re investigating on a family tree and WATO? provides a range of possibilities as to how two people may be related). Or the Inferred Segment Generator (you upload the segments that you and a DNA match share, and the generator will give a reading of the segments you don’t share). 

Text extracted from an article on DNA for beginners in the May 2023 issue of Family Tree magazine. Order your copy here.