Why DNA Test?

puzzle pieces

Sometimes I receive a question that just stops me in my tracks.  This past week, when a very experienced genealogist ask me “Why do you guys DNA test anyway?,” I was so dumbstruck as to be almost speechless.  Well, almost, but not quite, and I recovered quickly.

I did manage to stifle the urge to say “because we can,” but there would have been some truth in that statement.

For me, DNA testing is just a fact of life, ingrained into every molecule of my being, so I had to think a bit before answering.

Why do we do this anyway???

  1. Because we can!  Ok, I just had to say it, to get it out of my system.  But in reality, it’s true, because you don’t know what you don’t know.  And it’s low hanging fruit.  For between $49 and $99, at Family Tree DNA you can take a multitude of tests, but primarily  Y DNA, mitochondrial DNA and autosomal.  And with that, you can find out what it is that you don’t know.  The story of “Finding Anne Marie” is the perfect example. In fact, it has been turned into a book.
  2. We test to discover if we are related paternally (Y-DNA) to others of the same or similar surnames.  This also means that we can eliminate researching any lines that you don’t match.  So we do it so we can stop barking up the wrong tree, and hopefully, bark up the right one.  This article about Triangulation for Y DNA talks about surname matching.  This paternal Y test was one of the first and is still probably the primary DNA genealogy test done today.
  3. We can test relationship theories.  For example, let’s say that we don’t know who the father of our ancestor is, but there are 4 male candidates, all brothers, in the county at the time our ancestor was born.  Certainly, being rabid genealogists, we’ve already done the genealogy work, like check tax records, census schedules, church records and anything local, but now we need big guns because those resources didn’t reveal parentage.   This story about the Perez family in Guam and in Hawaii illustrates this beautifully and uses both Y DNA in combination with autosomal.  In the case of the 4 brothers above, we can search for their wives surnames in our matches and see if we can identify which couple by using the wive’s lines’ DNA.
  4. We test to find out about our ancient ancestry.  What “clan” or haplogroup did we come from?  There are a number of tests we can take to discover if we are Native American, for example, or African.  Some tests, like the autosomal tests, look back only a few generations, so they are broad, not deep, and some, like the Y and mitochondrial tests are very deep, going back hundreds of generations, but not broad at all, focusing like a laser beam on only that one specific direct line.  This article about “Proving Native American Ancestry Using DNA” tells about the various kinds of tests and how they can help with genealogy.
  5. We test to create a DNA pedigree chart that parallels and integrates with our genealogy pedigree chart.  Every ancestor and their DNA has an ancient story to tell that would be silenced without DNA.  In essence, we recover ancestry otherwise lost to us. How else would you ever find out that you descend from Vikings or Niall of the 9 Hostages?
  6. We test to better understand our genesis.  For example, we want to map our chromosomes to know which one came from which ancestor.  Ok, maybe number 6 only applies to geeky genealogists – but there appear to be a lot of us out there.  Kitty Cooper’s new mapping tool is quite popular.
  7. We test to find our family.  Just today, I “met” a cousin I match autosomally  and we discovered that we have some of the same “coureur du bois” stories in our Acadian families.  The difference is that she knew what they were, and I didn’t.  Click – that’s the sound of a puzzle piece falling into place.
  8. Some people test to prove paternity, or find biological parents or siblings.  Over the past couple of years, several great adoption tools and groups have been formed as we’ve learned to work more effectively with autosomal DNA.
  9. We test because it’s fun.  It adds another dimension and several more tools to the addiction we love, genealogy.
  10. Some test to discover more about their health traits.  For some, this health information is just a side benefit, but you never know when that health information will have a profound influence on your life.
  11. Some people want to participate in scientific research.  This is probably not a primary reason to test, but it does motivate a lot of people and this is one field where an individual can still actively participate and make a difference, sometimes a huge difference.
  12. Some people, like Lenny Trujillo, want to leave a legacy and what a legacy he has left.  This is one of the most common reasons people order the Personalized DNA Reports.  In some cases, their DNA line ends with them, but in others, it’s a way of leaving information for future generations.  Many people have these reports bound and give them as family-wide gifts.
  13. We test because we want to find the location in Europe, or wherever “the old country” is for our family, that our immigrant ancestors came from.  The Speaks family is a great example.  The American group had tested and confirmed the DNA of the original immigrant, but we didn’t know where the Speaks family came from, although we believed they immigrated from England.  Another Speaks family member, from Australia, tested, and matched the American group.  The difference was that our Australian cousin knew exactly where his English ancestor was from.  Through DNA testing, we found the home of our Speaks family in Gisburn, Lancashire, England.  You can read about it in “The Speak Family – 3 Continents and a Dash of Luck.”
  14. We want to prove or disprove our oral history.  In many cases, that history includes some type of minority admixture.  By minority, I mean not our primary ethnicity.  In the series, “The Autosomal Me,” I described in agonizing detail how to use tiny bits of DNA to do just that, and to identify which family lines contributed that minority admixture.  In my case, both Native and African.  Native had always been a part of our family’s oral history, but the African was initially a surprise.
  15. We test because we’re curious about where we came from, who we are related to, what they know about our ancestors that we might not.  As I’ve said before, “It’s About the Journey.”  Inquiring minds want to know…..

And it all starts with a DNA test!



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9 thoughts on “Why DNA Test?

  1. I wonder why people do ANY family history research, before doing a DNA test. I say this, because I spent the usual money with family Gen research in England, before I found out why my parents never mentioned my ancestors. Apparently my father is an NPE from a well known person, and was a family secret… so, now I have a totally new family line to follow, and with the help of this well known family.
    So, our DNA IS our family name, not the one we think. And even if there were no adoptions or NPE at all, there were no surnames prior to about the 12 th century anyway. Bear in mind that it is HIGHLY LIKELY, that in Europe and Britain, their were many epidemics, farming and mining accidents, housefires etc….and many children were taken in by neighbors, perhaps adopting the new family surname… but THAT family then inherited the childs Y dna as a family marker.
    So, in my opinion, paper trails are next to useless. DNA, is our surname. My own “paper” grandfather had four brothers, and all were killed in WW1, children taken in by friends, or children taking the surnames of a new marriage partner of the mother. And this is only in two generations.
    And then similar events happened in WW2… some fathers killed, “adopted” again.
    Unless of course, one is only interested in the family surname, regardless of the various surnamed fathers over the centuries. But I fail to see the point in doing so.

    • As someone who had good reason to doubt the paper trail story of my closest male relatives, I can sympathize with this view. Before I had access to the tools of genetic genealogy, I had an interest in old school genealogy, but I was afraid that my findings would be moot.

      Of course the paper trail is invaluable, putting the DNA evidence in context. But studying genealogy in 2013 without availing oneself of the latest technology is akin to studying biology at a university without learning about DNA. It’s really incomprehensible.

  2. Just today, a possible fifth-cousin reported back that the sample from her recently deceased father was inadequate to go from Y to autosomal. The company offered her 50% off on another test as compensation. I said “then take the test yourself.” She said “why.” I said because we have one test in each of two lines from her g-g-gf and I wanted a third as well. (Two others we are still working on.)
    I’m not sure she is convinced, so I sent her this link.

  3. Through DNA, I have so far met a 1-2nd cousin on my Irish father’s side, and my paternal grandmother’s line from Ireland that could not be found except through DNA matching. The other exceptional thing is when I find a DNA match but can’t find a surname match I ask my new 2nd cousin if she has the match, and it narrows down which side of the family in which to look further. Before this I had no information on my father’s tree and now I have dozens of names that I am confident are my relatives, living and deceased.

    On a completely different note, my maternal ggrandfather was a southern plantation owner that (sadly) had slaves. Many took his name and so his name can be found on many paper records. An ancestor of one of his slaves wanted to know if she was in fact a relative and I was happy to be tested give her the answer. I was sure it was going to be positive (and would welcome a new cousin) but the test confirmed that we did not share any common DNA.

  4. Thanks for great arguments to use on reluctant relatives! Genetic genealogy opens up so much more for us; I can’t imagine not using it.

    Thanks for sending posts even while you are on your “tour”.

  5. I asked a cousin from my maternal line and one from my paternal line to do the Family Finder to help me determine which side of the family my Family Finder matches were from. I have a total of 41 pages of matches – 5 pages in common with my maternal cousin; 4, with my paternal – and 32 pages that do not match anyone. Help! What do I do next?

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