DNA testing and how it supports family history is one of the hottest topics in the field of Family History Research. Jim Brewster, Group Project Liaison at FamilyTree DNA recently spoke at RootsTech 2016. He explained the top 10 reasons to take a DNA test. Among other things, they include contributing to breakthrough research, learning the ethnic makeup and migrations of your ancestors and discovering new cousins.
As a reminder of your biology class, you get your DNA from your parents. DNA tests analyze the chromosomes that are found in your cells. You have several types of DNA that can be used for genealogical testing, including mitochondrial, autosomal and X and Y chromosomes that determine your gender. Think of pictures of tightly wound thread-like structures (shown below).
There are three main types of DNA testing, including: autosomal DNA, YDNA and mitochondrial DNA (mtDNA).
Autosomal DNA testing is the most common test and the results provide you with your ethnic background percentages by regions and subregions. In addition, autosomal DNA test results will provide you with family members (who have also been tested) who share common ancestry in the last five generations. The results also show how closely they are related to you, based on your DNA results. Autosomal DNA test results include both your maternal and paternal family lines.
YDNA testing traces the direct paternal line for men who get this test. If you think of your family tree in landscape mode, YDNA testing traces the direct male line across the top of your tree or pedigree chart. Similar to other DNA test results, YDNA test results provide a list of others who have been tested and that have a common male ancestor within the last 25 generations. YDNA testing also provides the haplogroup and sub-groups that you belong to and the migration patterns of the haplogroup. For YDNA testing, you can choose to test 37, 67 or all 111 DNA markers — as you might expect, the more markers you choose to test the more detailed your results and the more you can expect to pay for the testing. FamilyTree DNA allows you to upgrade at a later time, from one level to the next level by paying the difference in price.
Mitrochondrial DNA testing traces your maternal direct line for up to 52 generations. Similar to YDNA testing for a man’s direct paternal line, mtDNA test results can provide both the haplogroup and ancestral migration routes of your maternal line. And like other DNA testing, mtDNA testing provides you a list of others who have been tested and to whom you are related to and how closely related.
All three types of DNA test results can help your family history efforts by confirming things you already know as well as connecting you with others. Many people are able to break through the all too common brick walls with the help of a second- or third-cousin whom they have never met.
DNA testing is available from FamilyTree DNA and several other companies. If you’ve already had your DNA tested, consider uploading your results to additional DNA databases to learn even more and to find additional cousins. One such DNA database that is relatively new, yet growing rapidly is DNA.land — DNA.land is both the name of the project and its URL web address. DNA.land accepts DNA file uploads from FamilyTree DNA, Ancestry.com and 23andme. The consent agreement is both short and simple enough to understand in a few minutes. 90% of DNA.land users have one or more cousin matches — and this will grow as more people upload their autosomal DNA test results.
Finally, consider joining a group project to learn even more. Group projects are organized by surnames, haplogroups, geographical locations or a combination of these. Try an internet search for your surname and DNA — in my case, I searched for “Davidson DNA” to find my surname group project. Each group project has a volunteer administrator that can help you get started.