What is a Genealogy DNA Test?
A genealogical DNA test could help you find genetic relatives and expand your genealogy research. It is another tool you can use to find family members who know more about your family. It does not replace your paper research - it's another set of data.
For more introductory information on the types of DNA tests, have a look at DNA Basics, part of the Getting It Right Series.
The International Society of Genetic Genealogy (ISOGG) is the authoritative site on all things to do with DNA testing for Genealogy. Their Wiki has a huge amount of useful information, including for those new to DNA testing.
It is important to know what you want to get out of doing the DNA test. DNA does not lie and some people get unexpected results which become life-altering.
Gail Riddell discusses these in her presentation slides:
Who to Test?
Most people test themselves. There are other people in your family who can improve the information you can receive from DNA testing.
Always ensure that family members are fully informed and give willing consent before doing a DNA test.
- Your parents (or grandparents) - you only inherit half of your parents' DNA. Testing them will get you all of their DNA.
- The oldest person available in your family such as (great) aunts and (great) uncles. Aunts and uncles will have a different set of DNA to you. Like your parents, they will have more DNA from their parents than you will have.
- Your siblings - they will have inherited a different set of DNA from your parents (unless you're identical twins).
How to Test
DNA Sample Collection
There are two main types of DNA sample collection:
- The Cheek Swab method where the user gently scrapes the inside of their cheek
- Saliva method where the user spits into a tube.
Older people find producing saliva difficult so may prefer a cheek swab.
It can be quite overwhelming when your results are returned.
- DNA does not lie, so be prepared for the unexpected.
- Watch the latest videos from the company you have tested with.
- Take your time - there is no rush.
Interpreting Your Autosomal Test Results
To make sense of your results, you will need three pieces of information:
- The size of your match
- Measured in centiMorgans it gives an indication of how closely you are related
- See the Shared cM Project at DNA Painter for indicative ranges and possibilities.
- Your Shared Matches
- These are people who have DNA in common with you
- If you know who one or some of them are, it will indicate which branch of your family your Match is on.
- Family Tree
- This could be your family tree, your Match's family tree or another online tree
- This will allow you to look for where your Match fits into your mutual family based on the approximate relationship and the likely branch of the tree
- Some of the testing companies have tools which compare family trees and make suggestions. (Note: they are suggestions, check them carefully!)
Lost Cousins have put together a Masterclass which gives further information (focused on Ancestry.com but applicable to others).
The Leeds Method
This technique for figuring out where your matches fit into your family has different names - grouping, clustering, colour coding. It was developed by Dana Leeds - her website gives an explanation of how to do it.
Some of the testing companies have provided tools to make the process easier:
If you want to connect with a family member and DNA Match you haven't previously researched with, testing companies will give you the ability to contact to them.
Reach out to them with a brief friendly note, something along the lines of:
"Hello..................., My name is ................................ from Waikamokau, New Zealand. According to our DNA results with.................. we are "2nd cousins" I looked at my tree and it looks like we are related through ...................... & ...................... I would love to connect with you and compare notes. Kind Regards"
Make notes of whom you have contacted.
The testing companies all have websites and videos to help you navigate their systems. They're a great place to start if you're having trouble with their websites.
The best way to figure things out can be to talk with someone who has already tested. Some NZSG Branches have DNA groups. If they don't, they may have a knowledgeable person who can help you. Find your nearest Branch.
DNA Bootcamp - these videos (available to NZSG members) give a good overview of DNA. The Testing Company-specific ones have dated a little, but the concepts these companies are using remains the same.
For other online help, see the links below.
Uploading Your Data to Other Sites
Once you feel comfortable with the original site on which you tested, download your raw DNA from that site and upload it to other sites, such as:
GEDmatch provides Autosomal DNA and genealogical analysis tools for amateur and professional researchers and genealogists. Most tools are free, but they do provide some premium tools for users who wish to help support them with contributions. You will need to upload your DNA and / or genealogical (GEDCOM) data to make use of the tools here.
Family Tree DNA you can transfer your AncestryDNA, 23andMe or MyHeritage autosomal DNA to Family Tree DNA and discover new matches. There is a cost involved to use all the tools.
My Heritage allows your Autosomal results to be transferred. There is a cost involved to use all the tools
Living DNA allows your Autosomal results to be transferred. It has a partnership with FindMyPast.
Your data will download from your testing company as a .zip file. DO NOT unzip it. The upload companies want it zipped!
Get your parents, grandparents, and siblings tested. You get 50% of each parent’s DNA. Since DNA is inherited at random, siblings and cousins may have inherited segments of DNA that you didn’t, so they could match people you don’t. Testing older generations helps extend your research further back in time and target family lines more specifically.
You may also like to branch out into Chromosome Mapping to build a map of which ancestor provided the DNA on specific chromosomes. This is an advanced technique with the tool developed by Jonny Perl available on the DNA Painter website. Jonny answers the question of Why map your chromosomes?
This is not an exhaustive list but includes many experts in the field of DNA.
Facebook Groups and Pages
The NZSG Library has a number of books on DNA, including these:
Blaine Bettinger's book "The Family Tree Guide to DNA Testing and Genetic Genealogy"
Kerry Farmer's book "DNA for Genealogists