What is mtDNA?

Mitochondrial DNA (mtDNA) is passed down from a mother to her sons and daughters. However, only daughters pass it on to their children. So, whether you or a man or a woman, you will have received your mitochondrial DNA from your mother's mother's mother etc (i.e. your direct female line).

Mitochondrial DNA can be used to connect with distant cousins on your direct female line.

It has a "reach" of about 200,000 years and thus can be used for exploring your deep ancestry on your direct female line. This will give you an indication of the route that your direct female line ancestors took when they left Africa during the last human migration.


  1. Being new to this, I'm confused with so much info. I am a woman. My brother and I are my deceased mother's only living relatives. For the most information on my ancestors on my mother's side, would it be best to have my brother (rather than me) tested for mtdna? Would there be an advantage for both of us to have the test?

    I will be grateful if anyone can advise us.

    Thank you,

  2. Your brother and you probably have the same mitochondrial DNA because you have the same Mother. Your brother would have his Father's Y chromosome, the other bit of DNA that is based down without mixing with other DNA. You would share some autosomal, or mixing DNA but you will have inherited somewhat different bits. A brother shares about 25% of your DNA, and each of you share about 50% of each of your parents DNA, but not exactly the same genes. So if both of you take tests your Brother could take the Y chromosome test (which you can not) and you would learn a bit more about your parents and their ancestors because of the bits that do not match exactly. Depending on what you want to learn and which tests you order (and from which companies) you might learn enough to make it worth your time and money. Only you and he can judge what are willing to spend in terms of time, effort and money. One think you can not get from the tests is the genealogy you need to combine with the dna results to make meaningful progress. It is best to do as much genealogy as you can alongside the dna testing. The more you are able and willing to share, the more people will be able to share their research with you. A key mistake is to underestimate how much how have to do to get results. Sometimes you will luck out and find a very close relation. Sometimes it may take years of work and you will still have a hard time. Do you know your grand-parents' basic information? Do you know any aunts or uncles or cousins, even though they may be deceased? All bits of useful information can prove very useful but if you can't do the work or are afraid to share family history and genealogy, you may not get far.

  3. if i am understanding this then the only test which would include my maternal grandfather and his line would be the family finder?

  4. also I transferred my ancestry DNA to FTDNA, is it worthwhile repeating the family test with FTDNA or wasting money?

    1. No need to repeat it - you would get similar results. Better to spend the money on another family member.


  5. DNA data collection from Asian & SE Asian countries is very minimal as compared to N. America and Europe. As a result companies like Ancestry DNA would conclude that certain percentage of the DNA comes fro Vietnam, Philippines or S.E. Asia, which is absurd before there are hundreds of ethnic groups in Vietnam, S. E. Asia or Philippines. They should say, in all honest, that there are insufficient data to substantiate what ethnic group that DNA comes from. Honesty is the best policy.

  6. I'm contemplating having my MTDNA tested. I've already had the basic done years ago with MFTDNA. Not sure if I'm understanding the process correct. Will matches only be found with others that did the MT testing or would matches be found from the general DNA pool? My mom's grandparents were from County Wexford and Meath. Also would I have to do a new kit?