Finding Your Ethnic Roots: Not as Simple as the Ads Make it Look
This article was written as a guest blog for Adoption Reunion Search & Support by some of our amazing Angels. For more information on how to become one of our guest bloggers, please contact us here. If interested in volunteering as an Angel, please click here to apply.
The drive to explore genealogy is fueled by the inter-generational or ancestral self, and the quest for self-knowledge through knowledge of our ancestors. This helps us to understand and orient ourselves in the world and in time, which then affects confidence and decision-making in all aspects of life.
Picture, if you will, a young woman receiving her DNA results from a major testing company. All her life, she's grown up hearing stories from her parents about their Swedish roots. She fully expects to see her ethnicity report to be mostly based in Scandinavia.
An unexpected surprise appears on the screen.
The next day, she purchases a full traditional costume to reflect her Irish heritage.
It's not that simple.
In reality, when you get your DNA test results from any of the private testing companies, the ethnicity pie chart or map that is shown is not a complete or entirely accurate assessment of your ethnic roots. This might be shocking news and might even prompt you to question truth in advertising or even the accuracy of DNA testing in general.
Do not worry! What is really going on here is that the testing company is making an estimate or an educated guess about your ethnic background as compared to the testing pool they already have. The good news is that you can get a much more accurate estimate for yourself if you learn a little bit more about the science behind the attractive looking maps and pies.
What is Admixture?
Admixture is the scientific term for genetic ethnicity percentage estimates. Based on user-submitted information, archaeological samples and thorough data analysis, admixture projects attempt to approximate the origin of your ancestral lines and estimate what percentage of that DNA has been passed down to the individual tester. While admixture project algorithms are based on scientific data, they are only accurate as compared to the available DNA testers who have reported their genetic ethnicity, and the archaeological samples contributed to the project. These tools are incredibly helpful for your genetic genealogy research if you know what you're looking at and what to look for.
What can your admixture estimate help you with?
There are a few notable populations that are lacking in and could benefit from a more complete understanding of their heritage in order to build up their sense of ancestral self. Americans in general often have questions about their ancestry, since the United States is comprised primarily of immigrants who at some point or another came here looking for a better life. Usually that comes along with leaving a lot of things behind, some of which may have even been destroyed, including facts about lineage. African Americans can begin to find answers from specific admixture projects that work to pinpoint tribal groups, restoring a sense of belonging that was taken from them through slavery. Adoptees can find clues in their admixture results that can lead them to their biological families and corroborate with information in their non-identifying information documents. People with unknown parentage can get insight into what to expect when they look at their projected cousin relationships between DNA matches.
Admixture estimates can also help you to discern how many generations back your relation to specific ethnic groups might be. For example, if the DNA test you took was autosomal only, and you had an 7th great grandparent who was Native American, you may not see any measurable percentage of Native American showing up in your admixture. If you had one 5th great grandparent who was Native American, you might be able to see a small wedge of your pie attributed to Native American ancestry with certain estimates, but maybe not in other ones. If your family tree is filled with generation upon generation of Chinese ancestors, but you had one great grandparent who was from England, that would make it likely for you to see about 12.5% of your admixture represented as European. These numbers aren't set in stone due to the random distribution of DNA segments. Full siblings may all have slightly different percentages show in their admixtures. If a population that you know is represented in your genealogy doesn't show up in your admixture result, you may not have inherited that segment of your ancestors' DNA.
All admixture projects are maintained by different groups of researchers and draw from different pools of data. Every major private DNA testing company uses only one admixture project for their ethnicity predictions. This means that if the same person tests on two sites, the ethnicity results will look slightly to very different. The admixture projects used by these major private testing companies paint with a broad brush and don't give specific regional information. When testing companies give you results reflecting a region, it usually points to entire chunks of continents. If you have a measurable percentage of ethnic background from an untested or under-tested population such as a smaller Native American tribe, most tests will simply fail to show that in your results at all. The reason for that is that is that it's just not in their test pool, so they have nothing to compare it to.
Do-It-Yourself with GEDmatch for More Accurate and Specific Results
Anyone who tests with any major company can upload their raw data to GEDmatch for more advanced tools. (For instructions on how to download your raw data for upload to GEDmatch, see the help section for the company you tested with.) Since GEDmatch is a crowdsourcing-style project, multiple independent scientists and researchers are able to have their DNA project included on the website and make it available for the general public to use and contribute to. These researchers often have cutting-edge ideas and focus their work on a variety of specific populations. For example, the Ethiohelix project has a special focus on regional populations throughout Africa. If you were surprised to not see Native American results in your ethnicity pie from your private testing site, use one of the Eurogene's projects to see if "Amerindian" shows up in your admixture. These projects are constantly being updated and fine-tuned as the researchers locate genetic samples and segments that they can trace to specific regions. This means that every time you run an ethnicity estimate, it is only as accurate as the most recent project update. If you returned in a year to run the same projection, it may well have changed even though you are using the same DNA kit you used a year ago! As worldwide DNA research becomes more specific, your personal ethnicity estimate will also become more accurate.
To put these tools to work for you, find the admixture tools on GEDmatch after you have uploaded your raw data from your testing site:
Pick the project you want to use. MDLP Project is a broad, world-based project that covers large global areas and is a good place to start if you have no idea where you're from. Eurogenes focuses primarily on Europe and the new world. Dodecad covers Asian and African ancestry. HarappaWorld is specific to South Asian populations. Ethiohelix covers African ancestry, and is great for people of mixed ethnicity with any amount of African descent. PuntDNAL and GeodrosiaDNA's sample populations are mostly comprised of archaic DNA samples found at archaeological sites.
After you've picked your project, input your GEDmatch kit number (you can find this on the home page of GEDmatch after you log in) and choose the calculator model if the option is there. Some projects have sub-projects. For example, the numbers at the end of the Eurogenes calculators indicate how many populations the project is broken down into. K13 will give you a more general admixture result, and K36 will break your admixture down into far more specific regions. For more information about what each calculator does, refer to the website of the project.
Wait about 30 seconds to 2 minutes, and you'll see a screen that looks like this. This example is using Eurogenes K13. Notice the large slice of North Atlantic ...
...and this is the same kit run with Eurogenes K36. It looks completely different because the larger regions from 13 are broken down into smaller, more specific regions.
Something About My Results Surprised Me!
Throughout human history, civilizations have migrated, made war, and made peace with each other. Ethnicities have mixed in ways you might not know about. If your family is from Greece, and you see Turkish ancestry in your admixture, this can be explained with history. Other reasons your admixture might look different from what you're expecting is because of non-paternal events (NPE's, or the occasion that a child's biological father is different from what is told or recorded) or family legends turning out to just be legends.
It's important to remember that this doesn't have to be a bad thing. Your genetic ancestry does not supersede your cultural upbringing. Nature and nurture can work together to help you gain a clearer understanding of yourself and your family.
Using admixture results to supplement your genetic genealogy research can answer questions that you might not have realized that you needed to ask. Understanding how to employ the latest available tools to more accurately interpret your data, while confusing at first, will help to bring your ethnicity estimate into sharper focus.
Adoption Reunion Search & Support is very thankful for our guest bloggers as we are all full of knowledge to share! Thank you Anthony and Lee for sharing your insight regarding DNA tools and helping our ARSS community as Angels. If you are interested in guest blogging or have questions regarding the different websites available to you, please message us here.