Explore your ancestry with a free trial!

Genealogy Clips

What is Autosomal DNA?

🎧 Listening to the Podcast on YouTube or iTunes.

Are you familiar with autosomal DNA? If you are not, you should be. It is one of the most important, and common, ways of using DNA to add to your family tree and to improve its accuracy. Now is the time to learn about autosomal DNA and what it can do for you in your genealogical research.

While Y-DNA traces only ancestors on the male line of your family, and mt-DNA traces only ancestors on the female line, autosomal DNA traces both sides equally. There are parts of our DNA that researchers have not yet discovered a purpose for, and this DNA was commonly referred to as “junk DNA” in the past. However, genealogy experts soon discovered that this so-called junk DNA could be used to reveal family relationships for both men and women. This was an improvement on the Y-DNA test that only men could use, and the mt-DNA test that traced females who usually changed their last names upon marriage.

An illustration of the inheritance pattern and phenotypic effects of an autosomal recessive gene.

Anyone in your family can take an autosomal DNA test. It will also show you people who are related to you on both sides of your family. Most DNA testing companies today do only autosomal DNA testing, as it is the most useful type of testing for the most number of potential customers. A few companies still do Y-DNA and mt-DNA tests for those who need those tests particularly, but autosomal DNA testing is still the most commonly used test. It is also highly affordable because it is used so much by so many customers.

When you take an autosomal DNA test, the testing company will show you matches to other people in their database who have also taken the test. These matches may be on your father or mother’s side of your family. In most cases, you will have to contact the ones who have agreed to allow contact from their matches and discuss your family trees to determine which side they fall on. Sometimes, it will be obvious because of a particular surname, or because you see they are also matched with someone you already know.

If you can get one or both of your parents, grandparents, or anyone who is a sample from both sides of your family, you will get much more accurate results, and some sites, like 23andme, will actually be able to tell you which side of the family that person matches on. The more of your relatives who test, the more accurate your results will be for your matches.

When you meet your matches online, you have a very good chance of learning new family tree information you previously did not know. You might even find someone who has a family Bible or old family photographs and who is willing to share them with you.

Basically, when you have your autosomal DNA tested, you are able to find out much more about your entire family than with any other type of DNA test. It is worth it for any genealogist to have this test done.