Questions to Ask Before Doing A DNA test

I recently joined a new Facebook group started by Thomas MacEntee called “DNA Do-Over” in the About section the description of the group is as follows:

You did a DNA test and you have your data, so what's next? Put your DNA data to work with DNA Do-Over, a closer look at your DNA!

Each month we will tackle ONE topic with easy-to-understand, non techy language that isn't too scientific. We will learn how to download our DNA test data, transfer it to another DNA testing vendor, transfer it to GEDMatch, learn terminology such as SNP and centiMorgans, etc.

Since I learned a lot from his Genealogy Do-Over group I was pretty sure I would find this group helpful as well so joined the group.

Note: if you don't do Facebook or don't want to join the group you can read Thomas' posts on his blog at Abundant Genealogy or sign up to join his email list. However then you miss out on the discussion from the members, and for me I have learned so much from the discussions from other members on this journey I wouldn't trade being a member of the group for anything!

This week there was one such discussion that I participated in. One member posted saying they were going to give a 7 minute presentation based on two questions. One, What are the questions one should should ask before doing a DNA test; and two, what are the questions one should ask before hiring a Genetic Genealogist. This post sparked an interesting and lively discussion. And that made me think it might make for an interesting blog post. I am going to limit this post to the first question.

First thing that was agreed upon was that 7 minutes really wasn’t enough time to adequately cover even one of those questions let alone both, that really both deserved their own 45-60 talk. There is just so much information, and misinformation, out there on what DNA testing is, and what you can hope to get from doing one or more DNA tests. I will try and touch upon the topics brought up in a general way in this post. In the future I may revisit the topic and expand on one or more of the points in separate posts.

First question to ask is: ”What do you want to find out by taking a DNA test?” This will help direct you to picking the right company to use and which test to use.

Are you only interested in your ethnicity? In my opinion then any of them are an OK option. Why do I say they are just OK options? Because at this point in time the ethnicity aspect of DNA testing is a new science with a limited sample base, thus thy are not 100% accurate and are subject to change. See my post from 17 Dec 2017 to learn more. Also be aware that we have inherited different bits of DNA from our Ancestors than a sibling will have inherited. So your results will be different even from a sibling (unless you are an identical twin, then their results should be the same).

Are you looking for health info? Then you probably want to do the 23andMe Health + Ancestry Test. Although you can do a test from one of the other companies and then upload your raw DNA to promethease.com and they will run a report for potential health issues that are in your DNA. Just remember that only a fraction of the dna has been mapped for how it may or may not affect our health. Other genes may also affect whether or not someone gets or doesn't get a certain disease or conditions. These unmapped genes may increase OR decrease your risk to develop a disease. Other factors like diet and environment have an affect on our health that will impact our potential to develop a disease. So do NOT panic if your report shows you are at increased risk for something, and conversely do NOT disregard symptoms and your family health history if the report shows average or even decreased risk to a specific disease or condition. Once you get a health report you should ALWAYS share it with your primary health provider and discuss what if any changes you might want to make in your life to minimize risks, or if there are further tests your doctor might want to run based on the information in the health report.

Are you looking to find info on your direct male line? Then you will want to use a Y-DNA test (if you are a female you will need to find a male ancestor on that line to do the test since only males inherit the Y chromosome.) Do you want information on your direct maternal line? Then you will want to do a Mt-DNA test, both males and females can do this test. Only one sibling needs to take the MtDNA test. Unlike the autosomal test where there is variations in what DNA each child gets from each parent, the MtDNA is usually passed down from mother to child unchanged. At the moment only major DNA company that offers the Y-DNA and Mt-DNA tests is Family Tree DNA (FTDNA). They also have projects for surnames and locations. Sometimes the projects will offer discounted tests, and occasionally free tests, so check them out before buying a test. The people heading up the various projects will also offer advice as to the best level for you to test at, so again talk to them before buying.

Are you looking to find living cousins to help break down a brick wall? or to verify the paper trail? or just to help leaf out your tree further? Then the Autosomal test is for you. It gives you the broadest number of matches. Both Ancestry and 23andMe are Autosomal tests. My Heritage, Living DNA and Family Tree DNA also offers the autosomal DNA test. Most people suggest you test at either Ancestry or 23andMe (or both) first then upload your raw dna to My Heritage, Living DNA and Family Tree DNA. You can upload to all 3 for free, although FTDNA has a small one time fee to view the full results. Gedmatch is another site you can upload to for free and if your matches from other companies have also uploaded their DNA to Gedmatch you can compare your DNA even if you haven't tested on the same sites. The basic tools on Gedmatch are free, although they do have some premium tools available for a small monthly fee.

I have tested at 23andMe (2011), then Ancestry (2012). I uploaded my raw DNA to Gedmatch, FTDNA and most recently to My Heritage. I have not uploaded to Living DNA, yet. I have family members who have tested for me on Ancestry and others who have tested for me on 23andMe. Most of those have also transferred their raw DNA to Gedmatch.

In my personal research I have found Ancestry to be the most helpful, only because that seems to be where most of my dna matches have tested. For my children, 23andMe has been great because they have had a number of 2nd cousins who have tested there. Your results will vary depending on where your cousins have tested. I have not spent as much time working with my matches on FTDNA or my matches on My Heritage.

One point that was really emphasized in the discussion was being aware that DNA TESTS CAN REVEAL SURPRISING THINGS! Such as an unexpected sibling or cousin. Another possibility is a person who is a close family member that should be a DNA match not being a match. By close family member I mean 2nd cousin or closer. By 3rd cousin there is 10% possibility you ARE related but do not share DNA. By 4th cousin match there is a 50% possibility you are related but don't share DNA. If this happens to you the FIRST thing to do is verify that they have tested at the same company you tested at. They can not and will not show up as a match if you haven't both tested at the SAME company!!! These types of surprises have happened to people, sometimes with devastating results. This is a possibility you should consider BEFORE testing. DNA testing has a way of outing family secrets.

Again back to the point that we received differing amounts of DNA from Common Ancestors. Just because we get 50% of our DNA from each of our parents doesn't mean we get 25% from each of our grandparents or 12.5% from each of our great grandparents.

Think of it it this way... Our parents' DNA are 2 separate bowls of DNA marbles. We take half our DNA marbles from our Dad's Bowl and half from our Mother's Bowl. The bowls magically refill and our sibling takes half of their DNA marbles from Dad's Bowl, and half from Mom's bowl.... The probability that we each got the exact same mix of marbles is pretty astronomical due to the number of possible combinations. It is possible that I get no DNA from a 3x great grandparent that one of my siblings or a cousin did get DNA from.

Another point that was brought up was DNA testing will NOT magically fill in your tree. There is still work involved in evaluating matches and how you fit into each other's trees. DNA is just another Tool in our Genealogy Toolbox, it is NOT a magic wand!. You will see that you share dna with your match, and it will suggest a possible level of how you might match. For example, predicted 2nd cousin with possible range of 2nd-3rd cousin. Ancestry does have Shared Ancestor Hints. These hints pop up when both you and your DNA match have the possible common ancestor in your trees. However the name has to be the same and the dates have to be close enough the algorithm can tell they are the same person. I have a 2x grandmother that in some records she is listed as Drusilla, others as Rozella, or Rose. I have had some hints that show us related to our 2x great grandfather but not the 2x great grandmother because of the difference in how we have her name listed in our trees. It is even worse when someone uses nicknames in quotes in the name, or titles in the name. The algorithm just won't recognize them as being the same person.

Privacy of tester was another topic brought up, but that is a pretty big topic in and of itself and probably deserves its own post. There are a number of good posts on the topic already out there. The Legal Genealogist covers the topic periodically, as do other Blog Authors. A web search should bring up some good posts on the topic. I will cover it sometime in the future, after I have done my own search to see what has already been covered.

I will close with the link for International Society of Genetic Genealogy. They have a LOT of information on Genetic Genealogy. I also want to include a link to the Genetic Genealogy Standards which covers the standards some of the leading Genetic Genealogist have developed. Finally, I would like to extend an invitation for you to join me on the Facebook group DNA Do-Over.