by Diahan Southard
DNA gave you the gift of your mother’s eyes or your father’s hair, your grandmother’s freckles or your grandfather’s nose. It’s fun and sometimes easy to see strong family traits connect the generations.
While these family attributes help you identify with the relatives you know personally or through photographs, the results of a DNA test for family history dig much further into the past. Read on to learn the basics about using DNA testing in your family history research.
Who Should Have a DNA Test Completed?
DNA testing provides a tangible connection to the past, which helps family history appeal to people that otherwise might not consider their heritage. So, in a best-case scenario, everyone would be tested. But, let’s be realistic; it is just not cost-effective to test every family member, so who should be at the top of your list?
Understanding just a little bit about DNA and how is inherited provides some clues about how to move forward.
As you may recall from your high school biology course, each of us receives half of our DNA from our mother and half from our father. So, what happens to the other half? The part you didn’t get? It is lost. Yes, lost! Some of that information might be recorded in your siblings’ DNA if you have brothers and sisters, but the truth is that much of our DNA record is lost with each new generation. Knowing that brings us to the conclusion that you need to test the oldest generation first. In short, anyone who is alive today, whose parents are not still alive needs to be tested (if their parents are alive, test them instead). Don’t forget about aunts and uncles. Great Aunt Hilda may be spry but it would be best to test her soon, especially if she is the last of her generation.
What Test Should I Take?
There are three different kinds of tests available for genetic genealogists.
- The Y chromosome test. This test provides a DNA profile useful for tracing a direct male line. Only men can use this test. It can help you trace your direct paternal line ancestry back 10 or more generations and help sort out related lines among a common surname. It can also help a male adoptee (whether in this generation or any past generation) identify a possible surname for his biological father.
- The mtDNA test. This test provides a DNA profile useful for tracing a direct female line. This moderately helpful test is most effective when you have a specific genealogical scenario in mind that you are trying to prove or disprove. (See scenario #2 at the end of this article for an example.) Anyone can take this test.
- The Autosomal DNA test. This test traces all of your ancestral lines, but it is generally helpful back only 5 or 6 generations. Anyone can take this test.
In general, each individual needs his or her own autosomal DNA test. You can then represent each surname in your pedigree chart by testing a direct male descendant of each ancestor with a Y chromosome test. This would be yourself, if you are male, or your dad or brother if you are female. This represents your own surname line. But then you can test your mom’s brother to capture her surname line, and your dad’s mom’s brother to represent her line, and so on. The possibilities are nearly endless!
Where Can I Order a DNA Test?
For YDNA and mtDNA testing, the choice is easy. Family Tree DNA is the only company offering YDNA and mtDNA testing for genetic genealogy. For the mtDNA test, you want to take the full sequence test. For the YDNA test, the 67 marker test is ideal, but the 37 marker test will suffice. You can always upgrade later if needed.
In the autosomal DNA testing category, you have three options for ordering tests: Family Tree DNA, AncestryDNA, and 23andMe. Each testing company has its own pros and cons. To help you make a decision, there is a comparison chart with information for each company. It should be noted that 23andMe focuses more on health purposes of genetic testing than on genetic testing for genealogy purposes. Because of this, 23andMe offers two levels of testing: one that includes health reports and one that provides ancestry reports only.
What it really comes down to is deciding which company is going to best serve your needs: a DNA match that will lead to a genealogical discovery. Of course, there is no way to predict whether you will find a DNA match, but using the largest database is probably gives you a better chance of that happening. Right now AncestryDNA has the largest database.
When Should I Order the DNA Test?
I love finding a good deal, and deals in DNA test kits can be found at both Family Tree DNA and AncestryDNA. Look for sales around the holidays, mid-April near DNA day, and Father’s and Mother’s Day, to name a few. You can always find deals if you attend a genealogy conference and purchase your test there.
Why Should I Include DNA Testing As Part of My Genealogical Research?
In case you haven’t been convinced yet, here are a few scenarios that demonstrate how useful DNA testing can be in your family history research.
Ancestor dead end: Adam Shaw, born in 1854 in Virginia.
Traditional Research Summary: You have found several other Shaws in nearby counties, but you haven’t been able to determine if they are connected to Adam or who Adam’s parents are.
Suggested DNA testing route: Find a direct male descendant of Adam to take the 37 marker YDNA test. This will be a living man with the Shaw surname.
Possible outcome of testing: You see that your YDNA test matches other Shaws who have tested, including a descendant of a man named Robert Shaw of Virginia.
Next Steps: Work with these YDNA matches to see how your lines may connect. Actively recruit direct male descendants of the other Shaw lines that you think you might be connected to and have them take the YDNA test.
Ancestor dead end: Sarah, born in 1874 in Macon County, Georgia.
Traditional Research Summary: Sarah married Marvin Belle. Marvin is mentioned in the will of Harold Reynolds, who was his neighbor. You suspect from other research that Sarah was actually the daughter of Harold Reynolds, but you can’t find any documentary evidence. Harold and his wife Margaret had four daughters that you can document.
Suggested DNA testing route: Find a direct maternal descendant of both Sarah and at least one of Harold Reynolds’s daughters, and ask them to take the mtDNA full sequence test.
Possible outcome of testing: Sarah’s mtDNA does not match the descendant of Harold Reynolds. This might mean that Sarah is not a daughter of Harold, or that if she is, she was not the daughter of his wife, Margaret.
Next Steps: You can try testing a descendant of a different daughter of Harold and Margaret, or you can try testing two descendants of Sarah and two descendants of Harold and Margaret (on any line) on the autosomal DNA test to see if you can identify a relationship.
Ancestor dead end: Josephine Randolf, born 1886? in Canada
Traditional Research Summary: Josephine is your maternal grandfather’s mother. You and your cousin Mark, also a descendant of Josephine, have been searching in vain for years to find out anything about Josephine’s parentage.
Suggested DNA testing route: Have both you and Mark take the autosomal DNA test. Any DNA shared between you and Mark will have come from Josephine and her husband, thus allowing you to target matches who may be related to this line.
Possible outcome of testing: You and Mark find four DNA matches who are predicted to be your fourth cousins and who have ancestors in the area of Canada where Josephine lived.
Next Steps: You can work with these fourth-cousin matches to try to identify a common ancestor between them that might lead to clues as to who Josephine’s parents were.
While there will always be more to learn and discover in the world of DNA testing, you should have what you need now to get started putting your DNA to work for you.