Our mtDNA Test

Our mtDNA test, called the mtFull Sequence test analyze the mitochondrial DNA, which is found outside the nucleus of the cell in the mitochondria. This test is also sometimes called the mtDNA test or the Full Mitochondrial Sequence (FMS) test. Mitochondrial DNA is passed down from mother to child, allowing us to trace the direct maternal ancestry through it.

Historical records are often inadequate for women’s history. Maternal DNA testing offers you the opportunity to at least partially overcome that barrier, and by testing your mtDNA, you will learn about your maternal heritage in both recent and ancient times.

Direct Maternal Line

Your direct maternal lineage is the line that follows your mother’s maternal ancestry. Fathers do not pass on their mtDNA to their children, so this line consists entirely of women. Your mtDNA can trace your mother, her mother, her mother’s mother, and so forth. It offers a clear path from you to a known or likely direct maternal ancestor.

For genealogists, this clear line means that they can trace two or more descendants of a single woman many generations back and compare their mtDNA results with the expectation of a match. For those interested in deeper ancestry, tracing the modern geographic origins of exact matches means that they can discover the anthropological origins of their own line.

Tracing Your Direct Maternal Line

How are we able to trace that maternal ancestry? We don’t have the DNA of everyone’s ancestors, so we’re not able to compare a tester to someone who lived 500 years ago and then match them to that person and everyone else who matches that person. The short answer is mutations.

Mitochondrial DNA doesn’t randomly recombine like autosomal DNA. It’s passed down directly from mother to child as shown in the image above. However, over time there are some changes to that mtDNA. If there weren’t any changes, then every person on the planet would have the exact same mtDNA and we couldn’t use it for genetic genealogy. 

Some changes happen more quickly than others. This makes it difficult to predict a Time to Most Recent Common Ancestor based on those mtDNA mutations but based on what we know about when certain haplogroup mutations happened, we can estimate this based on how much of your mtDNA is shared to a point.

Success in matching genealogically with an mtDNA test comes down to two factors:

• The number of mutations tested (the more of your mtDNA tested, the more specific your results and the greater the chance of finding matches). For genealogy purposes, a mtFullSequence is needed.
• The chance that others on your direct maternal line have also tested.

Tools & Features

mtDNA Matches

Your mtDNA may help you find genetic cousins along your direct maternal line. When we look at your mtDNA results, we look for differences in your mtDNA caused by small copy errors created in ovum. We call these copy errors mutations or polymorphisms. These mutations do not happen every generation, but they do build up over time. We compare those differences to the differences of other people in our database to provide a list of people who share a common direct maternal ancestor with you. Because of the slow rate of mtDNA mutations, the range of possible generations before you share a common ancestor with a match is wide. Your mtDNA matches may be recent, but they may also be hundreds or thousands of years in the past. 

Matching levels

There are three sections of mtDNA used for matching: HVR1, HVR2, and the Coding Region.

• HVR1 - Considered a low-resolution region. Matching on HVR1 means that you have a 50% chance of sharing a common maternal ancestor within the last 52 generations (or about 1,300 years).
• HVR2 - One of the two mtDNA hypervariable regions used in genealogical DNA testing. HVR2 is considered a high-resolution region. Matching on both HVR1 and HVR2 means that you have a 50% chance of sharing a common maternal ancestor within the last 28 generations (or about 700 years).
• Coding Region - Matching at HVR1, HVR2, and the coding region brings your matches into more recent times. It means that you have a 50% chance of sharing a common maternal ancestor within the last 5-16 generations (or about 125-400 years).

The mtFull Sequence test offered by FamilyTreeDNA examines the HVR1, HVR2, and Coding Region of mitochondria and is the highest resolution test available to genealogists. This test is also known as an mtDNA test, or the Full Mitochondrial Sequence (FMS) test. The closeness of a mitochondrial DNA (mtDNA) match depends on the matching level. Matches at higher levels are more likely to be recent.

Matching is Optional 

Viewing your matches and sharing your information with matches is optional. You can opt in and out of matching at any time.