Y-DNA Testing: The Useful DNA Test You Might Not Be Using Yet
Basics of Y-DNA testing
As I have worked with many people doing their genealogy, I have found that while many of them have done autosomal DNA testing, most of them are not taking advantange of the benefits of Y-DNA testing yet.
What is Y-DNA testing?
Y-DNA testing is a separate DNA test from autosomal DNA testing found on Ancestry.com and other sites. It has several differences from autosomal DNA testing:
- Autosomal DNA testing can generally be useful within 4-5 generations or so; Y-DNA tests can be helpful across many generations.
- Autosomal DNA testing can give you cousin matches in many lines of your family; Y-DNA tests only applies in one line of your family.
- Autosomal DNA testing gives broad and general results; Y-DNA testing is much more specific.
- Autosomal DNA tests can be taken by both males and females; Y-DNA tests measure a part of DNA that passes only from father to son so only a male can take the test.
- Autosomal DNA testing is currently offered by several companies including Ancestry.com, MyHeritage.com, LivingDNA.com, FamilyTreeDNA.com, and 23andMe.com; Y-DNA testing is currently offered only by FamilyTreeDNA.com.
Why would I want to use a Y-DNA test?
Y-DNA testing can help you narrow down specifically to just one line of your family which would be helpful in identifying a man's father. It has to be taken by a direct male descendant of the ancestor you are focusing on. For example, if I'm trying to find the father of my ancestor James Brown, I would need someone to take a Y-DNA test who carries the Brown surname and comes through the son of James, through a son of James's son, through a son, through a son, etc, down to the present. If you are not descended from the particular ancestor in your tree in that way, you can find a cousin or other relative to take the test for you.
The value of a Y-DNA test is that you will get cousin matches to individuals who also come through the same paternal line, so you are able to compare trees with this individual and try to find your common ancestor. Y-DNA stays relatively stable for many generations, so if you match closely on Y-DNA with someone, you are likely to share a common male ancestor with that individual somewhere in your family tree (though it may be many generations in the past and not always possible to identify who the ancestor was). Y-DNA testing can also help confirm that your paper tree is correct.
Y-DNA testing can be another tool in your genealogical toolbox. It's not often a complete solution by itself but when used in conjuction with autosomal DNA testing and careful genealogy research, it can be quite helpful in certain situations. To purchase a Y-DNA test, visit FamilyTreeDNA.com.
For an example of how Y-DNA testing can be used, see our article, Solving a Connecticut man's unknown parents using genealogical records and DNA.
Need help finding more records? Try our genealogical records directory which has more than 1.2 million sources to help you more easily locate the available records.