Mitochondria is the powerhouse of the cell, remember?
Well, it turns out that mitochondrial DNA testing is the powerhouse of direct-line female genealogy. The mitochondrial DNA (mtDNA) represents the best chance for women to find their direct female ancestor. It is transmitted directly from a mother to a child (a boy or a girl).
mtDNA test for women is the same as the Y DNA test for men. However, the mtDNA doesn’t analyze woman X sex chromosomes.
Why has mtDNA become so important in recent years?
Because the mitochondrial DNA is so very specific and useful for finding out your female ancestors.
Mitochondrial DNA analysis uses the distinct mitochondrial DNA that is placed separately from the main DNA in the nucleus of the cells, is much smaller, has a low frequency of mutation and is thus perfect DNA specimen for genealogy.
In fact, the mtDNA changes so little that the mtDNA a present-day woman has is almost identical to the mtDNA of their mother, grandmother, grand grandmother and so on for up to 50 generations.
That means that if Eleanor of Aquitaine, a Queen Consort of France and England from the 12th century, was your grand grand grand … grandmother, she would have a nearly identical mitochondrial DNA as you. All other DNA in the nucleus (autosomal DNA and XX chromosome) would change much quicker than the mtDNA.
We’ll delve into the mtDNA testing and explain:
- What is the mitochondrial DNA and how we analyze it?
- What does the mitochondrial DNA test show?
- How far back can mtDNA be traced?
- Best commercially available mitochondrial DNA tests.
What Is Mitochondrial DNA (And Why Do Only Woman Transmit it)?
Funny story about the mitochondria: The mitochondria was basically a bacteria that was captured by the early cells and the two lived together in a symbiotic state, helping each other. Mitochondria brought energy to the cell (‘powerhouse of the cell’) as well as its own mitochondrial DNA.
Why do only women transmit the mtDNA to the next generations?
Well, it all has to do with our reproduction system. The female egg cell has both DNA in the nucleus and in the mitochondria. When the conception happens, the male sperm cell enters the female egg and brings with it only the DNA is the nucleus.
Therefore the child has nuclei DNA from both mother and father. However, the mitochondrial DNA is only provided by the mother. And this mtDNA is transmitted from mother to child, and if the child is female, it is again transmitted to her children.
What adds to the accuracy of the mtDNA tests is that this kind of DNA doesn’t mutate as frequently as the DNA is the nucleus and that it is much smaller.
For comparison, mtDNA consists of less than 17.000 base pairs while the whole human genome has about 3.2 billion base pairs. It’s way easier to operate on way fewer base pairs that mutate way less.
How Sequencing Of mtDNA Works
If we check out the mtDNA tests from a more scientific viewpoint, we see that commercial mtDNA tests have an option to test one, two, or all three mtDNA segments. These include:
- Mitochondrial DNA coding region (the one responsible for carrying the most important DNA genes).
- Hyper Variable Region 1 (HVR1).
- Hyper Variable Region 2 (HVR2).
The HRV1 and HRV2 regions are usually the prime targets for sequencing and analysis. Many commercially available mtDNA tests focus on analyzing these hyper variable regions. The most basic ones test HRV1.
However, the analysis of the whole mtDNA (HRV1 + HRV2 + Coding Region) is beneficial because it gives you more precise and in-depth ancestry information, particularly about the haplogroups and the “where your ancestors came from” test (nicer, more details maps).
But testing the coding region comes with a twist. The coding region can contain information about your medical conditions and the diseases you might be more prone to have. Making medical predictions based on DNA is a regulatory challenging topic.
As of now, only the FamilyTreeDNA has managed to maneuver these regulatory waters successfully and have successfully brought their whole mtDNA test to the market.
What does the mitochondrial DNA test show?
The mtDNA test is designed to uncover one’s matrilineal ancestry. That simply means that you can follow the direct maternal line.
The mtDNA test shows and is most frequently used for the following two purposes:
- Genealogical research when you’re looking for your mother, grandmother and other relatives you share your mitochondrial DNA with. One of the more popular ways is to look for the most recent common ancestor.
- Tracking down your ethnic roots from the chromosomal-Eve that lived in Africa. By identifying your haplogroup you can see where did your maternal ancestors come from.
Be aware that the basic HRV1 test might be appropriate for looking at close relatives.
However, if you want to identify your haplogroup with the mtDNA test, you should look for more extensive tests that analyze both HRV1 and HRV2 as well as the coding region of the mitochondrial DNA.
How Far Back Can mtDNA Be Traced
Because mitochondrial DNA changes so little when transmitted from mother to daughter, it can be used to trace your maternal ancestors going back 50 generations or even more. This makes the mtDNA test one of the most reliable DNA tests around.
For genealogy purposes of building a family tree, the technique of analyzing mtDNA is most frequently used to find out who your 1st, 2nd and 3rd cousins are.
Moreover, mtDNA analysis can trace your origins as far back as the chromosomal-Eve.
Chromosomal-Eve was a woman that lived about 200,000 years ago in Africa from whom every woman on the planet can trace their roots. As the people started to move around in the early era of men (and women, obviously), the mitochondrial DNA started to branch out from Eve’s mtDNA. We call these branches haplogroups.
The mtDNA test can identify your particular haplogroup. This means you can follow the path of your ancestors from the original Eve right up to the modern-day.
In practice, the DNA testing companies use algorithms to provide you with those colorful maps that tell you where your ancestors came from and how much of a particular ethnicity you are.
So, in short, the ethnicity determining mtDNA tests can trace your origin back to as much as 200,000 years.
Best Mitochondrial DNA Tests
Similar to the Y DNA tests, there are DNA testing companies that specialize in mtDNA testing.
Obviously, there is also a major difference between the quality, accuracy, and price of direct-line maternal tests.
Not every test is appropriate for ethnicity and haplogroup determination and not every company, big or small, provides the mtDNA tests.
Ok, let’s check out which companies even have mtDNA tests and is they are any good.
Does Ancestry.com Do mtDNA Tests?
Ancestry.com is the biggest DNA testing company, surely they do have an mtDNA test, right?
That would make sense but, in fact, Ancestry.com doesn’t use mitochondrial DNA in their tests. They are the master of autosomal DNA with the biggest database of people who took the AncestryDNA test.
However, when it comes to more advanced tests, they do fall a bit short.
That is because they are big in genealogy and building family trees. The other part of DNA testing – finding our ethnicity and origins – is not something that Ancestry.com really does that well.
Of course, if Ancestry.com doesn’t do mtDNA tests, which company actually does them?
Does 23andme Offer Mitochondrial Tests?
23andme is a DNA testing company that is big in finding out your ethnicity. They are all about finding out “where do you come from” as oppose to Ancestry.com “who you are related to” deal.
Fortunately, 23andme does offer mitochondrial analysis as a part of their Ancestry Service test. Their test comprises information from autosomal DNA, Y DNA (for males) and mtDNA (for females) when analyzing what your ethnicity origins are.
It is a smart way of doing it – encompassing all available parts of DNA to better understand your ethnicity – but doing that does have a drawback.
In the case of the mtDNA testing, the drawback is that 23andme only analyses the HRV1 section of mitochondrial DNA (and doesn’t include HRV2 and Region Coding).
That is in part because they deem the analysis of HRV1 sufficient for ethnicity results and in part that they are very wary about touching the Region Coding part.
That’s the part that has information about our medical conditions and the FDA does have additional regulations when it comes to dealing with medical conditions information.
Nonetheless, the 23andme DNA test that takes the mtDNA into the account has one invaluable advantage: the 1000+ regions they can pinpoint your origins from.
In short, they have the most detailed ethnicity map of any DNA testing company and can give you very in-depth information about where you came from despite not performing the HRV2 and Region Coding mtRNA sequencing.
Ok, so who does the perfect and whole mtDNA testing?
FamilyTreeDNA – Best mtDNA Tests
FamilytreeDNA is a company specialized in the mtDNA as well as the Y DNA testing. For both the maternal and the paternal line they have the largest database (a big plus) and have developed several tests that can help you track your ancestors along the direct-maternal and direct-paternal line.
What is more, this is the only company that has a commercially available mitochondrial DNA test that analyses the whole mtDNA.
They do offer two options for their specialized mtDNA tests:
- mtDNA Plus test for $89. This one accounts only for the HRV1 and HRV2 regions.
- mtFull Sequence test for $199. This is the only test that takes into account HRV1, HRV2 and Coding Region data and is hands down the best mtDNA test on the market.
With the mtDNA Plus test, you can get some basic genealogical information as well as basic haplogroup matching. Despite not being as amazing as the mtFull Sequence, it still covers both HRV regions while the 23andme mtDNA test, for comparison, tests only one.
When it comes to which is the best company for mtDNA testing, and you’re looking Ancestry vs. 23andme vs. FamilytreeDNA, the FamilytreeDNA always comes on top just based on the mtDNA Plus test.
What is more, they do offer the advanced mtFull Sequence test that far outmatches any other mitochondrial DNA test. In fact, it is the only test that really sequences all parts of the mitochondrial DNA.
You can check both FamilytreeDNA tests here. You can clearly see that the advanced mtFull test costs twice as much but can give you a more in-depth insight into your ethnicity background as well as brilliant accuracy of the genealogy results for everybody who is building a family tree by tracking the direct-female line.