DNA tests are now an important tool for family history. They allow you to contact your 'matches' (people who might be close or distant relatives whose DNA matches yours). Some testing companies also give you powerful tools to analyse your results. My DNA tests have put me in touch with many relatives, ranging from 2nd cousins to (amazingly) a 6th cousin, who have shared information and helped me to confirm theories and fill gaps in my family tree. This page has my personal tips about DNA tests, and links to recommended reading. Links open in a new window.
I have done all 3 of these autosomal DNA tests, which are available to both males and females. If you test with AncestryDNA, I strongly advise you to transfer your results (free of charge) to FamilyTreeDNA. That link leads to instructions.
- Ancestry DNA test. Ancestry has the largest customer database; and they attempt to predict which ancestor you share with your match (which can be very helpful, but treat it as a theory, not a fact). As I said, transfer your AncestryDNA results (free of charge) to FamilyTreeDNA (note advantage no.1 below). WARNING! In August 2020, AncestryDNA will delete matches who share less than 8 cM with you, unless you have either added a Note, or added them to a custom group, or sent them a message. See this strategy to preserve small-segment matches.
- 'Family Finder' test at Family Tree DNA. Advantages include (1) This may take you back a generation or more beyond what you'll achieve with AncestryDNA, because FTDNA has results for people who tested long before AncestryDNA began; (2) It's easy to email your matches directly; (3) Your sample is stored in case you want to request additional tests (mitochondrial DNA and, for males, Y-DNA which is only passed from father to son); (4) There are good tools for analysing your results. For example, this site offers a Chromosome Browser (which isn't available at Ancestry); and when you upload a family tree that includes family members who have tested, and link each person's DNA results to that individual in your tree, FamilyTreeDNA's 'Family Matching' feature may show whether other 'unknown' matches are connected through the paternal or maternal side of your tree.
Living DNA test. Unlike the others, this allows you to break down your British / Irish ancestry within the last few hundred years into any of the 21 regions shown under 'Great Britain and Ireland' in the list of worldwide regions. My results have given me useful clues (eg, which counties to focus on when I'm researching my brick-wall ancestors).
The image on the right shows part of my results at LivingDNA. Most of their predictions fit beautifully with what I know about my ancestry, but Cornwall and Devon are unexpected, so maybe my 'brick-wall' ancestors came from there.
If you have done a DNA test elsewhere and would like access to LivingDNA's Family Networks service, you can upload a file that was produced by AncestryDNA, FamilyTreeDNA, MyHeritageDNA, 23andMe, Gene by Gene, or Geno 2.0 (National Geographic). See this explanation.
I also uploaded my raw data (free of charge) to:
- My Heritage DNA. Thank goodness I transferred my raw data to this site! An unknown distant relative in Germany, whose results are only at My Heritage, sent me a copy of my great-grandparents' marriage entry in a German church book.
- Gedmatch (which may find more relatives who have tested with other companies).
- Test older relatives as well as yourself. Some of my 4th cousins share enough DNA with my uncle to be listed as a match with him, but not with me.
- Test siblings. Because of the random way in which autosomal DNA is passed on, sometimes only one sibling will be detected as a match to a distant cousin. (My sister matches Barrie, our 4th cousin once removed, but I don't, because Barrie and I don't share a large enough DNA segment.)
- The more relatives you test, the easier it will be to figure out where your other (initially unknown) matches fit into your family tree.
- Link at least a partial family tree (your direct ancestors and their siblings) to your DNA results at each testing company.
- Check your account settings at each testing company.
- Before you contact your matches, read the advice in Tips and Tricks for Contact Success, and How to Send Ancestry Messages That Get Replies.
Recommended Reading about DNA
- The Family Tree Guide to DNA Testing and Genetic Genealogy, 2nd edition, 2019, by Blaine T. Bettinger (with free shipping worldwide). This plain-English guide explains what DNA tests are available, with up-to-date pros and cons of the major testing companies. It also explains how to interpret DNA test results and ethnicity, and how to use third-party tools to analyse your data.
- Advanced Genetic Genealogy, published 2019 (Debbie Parker Wayne). [This is for intermediate and advanced researchers. If you're a beginner, start with The Family Tree Guide to DNA Testing and Genetic Genealogy.]
- DNA Testing for Genealogy - Getting Started, Part Three explains autosomal DNA and its uses for genealogy (but see also Blaine Bettinger's book described above).
- Sharing Large Segments With a Match Does Not Validate Small Segments Shared With That Match (by Blaine Bettinger).
- Still Not Soup explains all the things DNA testing can help with, and the limitations of ethnicity percentages.
- Why we can misinterpret DNA results unless we have extra information (eg, about identical twins or a stem cell transplant).
- Up, Over and Down (by Judy Russell) clearly explains a strategy for targeted testing of Y-DNA (males) and mitochondrial DNA.
- Why doesn't a Y-DNA or mitochondrial DNA match also show up in your list of autosomal matches?
Saving money on DNA tests
DNA testing companies periodically offer discounts. I often mention them on Genealogy Discounts and Freebies, and on my genealogy page on Facebook and in my newsletter.
Image by jscreationzs (freedigitalphotos.net)