Help:Y-Chromosome DNA Tests

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Y-chromosome DNA testing (abbreviated yDNA or Y-DNA) and mitochondrial DNA testing (mtDNA) have been used by genealogists and scientists for years. Their value in confirming specific inheritance is well-established. In the case of yDNA, it's the inheritance on the direct paternal line. (For mtDNA, it's the direct maternal line.)

The most popular Y chromosome tests for genealogy are those offered by Family Tree DNA. See a comparison of the markers tested by various labs and a comparison of labs which offer advanced Y-DNA SNP testing. See the difference between haplotype and haplogroup.

What's Tested

These DNA tests are on the 23rd sex chromosome, the one that only men inherit. Sons get their yDNA from their father, who got it from his father, who got it from his father, etc.

To see your family's Y-chromosome inheritance, click to your DNA Ancestors page.

YDNA is inherited essentially unchanged. If two men are a close match, we know they are related in a genealogical time-frame.

Since women don't inherit the Y chromosome, only men can take yDNA tests. To learn about their direct-male line, female genealogists need to ask a brother, father, uncle, etc. to be tested.

Why to Test

The pattern of Y-chromosome inheritance is especially convenient for genealogists in the Western world: our surnames are generally inherited in the same way. Therefore, yDNA is often an important part of surname projects.

Testing companies such as Family Tree DNA will also provide you with matches, i.e. introduce you to other test-takers whose yDNA is close to yours. However, the frequency and utility of these matches pales in comparison to those you'll get from an autosomal DNA test such as Family Tree DNA's Family Finder. Most of the yDNA matches will be from a deep, pre-genealogical, common ancestor.

On the other hand, when you do match someone, you know that your common ancestor is on your direct paternal line. This is significant.

Moreover, yDNA testing (along with mtDNA and xDNA) are useful for targeted testing, when you want to confirm or reject a particular paternal or maternal relationship. See your DNA Ancestor Confirmation Aid page for how it can be used to confirm your family tree.

Usage on WikiTree

See the DNA Features page for how a Y chromosome test entered on WikiTree is attached to profiles, and how you can use special WikiTree tools and widgets to collaborate with your matches.


See also: Autosomal DNA Tests, Mitochondrial DNA Tests, X-Chromosome DNA Tests.



This page was last modified 15:07, 23 May 2017. This page has been accessed 7,059 times.