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When it comes to learning more about yourself and your family, you may be considering using an ancestry DNA test. Whether that’s because you’re looking for more information about unknown family members, your ethnic background, or to verify family tales, a DNA test can be a strong option for helping you learn more about your family tree.
What's in this Guide?
- How Do DNA Tests Work For Ancestry?
- What Can You Learn About Your Family From DNA Tests?
- How Can DNA Tests Tell Your Ethnicity?
- How Accurate Are DNA Tests For Genealogy?
- What Is The Best DNA Test For Ancestry?
- Can A DNA Test For Ancestry Help Find Relatives?
- Can DNA Tests Find Your Family Tree?
Disclaimer: Before You Read
It is important to know that your genes are not your destiny. There are various environmental and genetic factors working together to shape you. No matter your genetic makeup, maintain ideal blood pressure and glucose levels, avoid harmful alcohol intake, exercise regularly, get regular sleep. And for goodness sake, don't smoke.
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As at-home DNA test kits become more accessible and less expensive, more and more people are finding ways to use these DNA kits to locate half siblings, find their birth families, and discover more about their Native American, Jewish, or other heritage.
How Do DNA Tests Work For Ancestry?
Don’t worry — even if you’re not a science wiz, you can understand the basics of how DNA tests for ancestry work.
At-home DNA test kits that are used to learn more about your family tree rely on an anonymous saliva DNA sample that you submit to their laboratory. While DNA tests can also use blood or hair to get results, you won’t need to worry about pricking your finger or plucking a few hairs for at-home DNA ancestry tests.
That means that after you order and receive the kit from your selected DNA testing company, you’ll register the kit and receive an anonymous code that links your sample with the results. Next, you’ll need to use the provided cheek swab (which picks up DNA cells from inside your cheek) or spit tube to collect your DNA sample before sending it back to the DNA test company.
After the laboratory receives your ancestry DNA sample, the genetic testing company will begin its analysis of your DNA. All DNA ancestry test laboratories use computers that digitize the strands of DNA from your saliva or cheek swab.
DNA is broken down into a string of four randomly repeating letters — C, G, A and T — called nucleobases, that combine in individual chains to create different parts of your genetic makeup, including traits such as hair color, height, ethnic background, and more.
Computer analysis of your specific chains allows scientists to pick out the patterns of these four letters, from which they can determine certain things about you — in the case of ancestry DNA tests, things such as your ethnicity, genetic heritage, and if your DNA is related to other anonymous DNA samples that have been submitted.
But how do scientists know that you’re related to other people? Well, that’s because DNA ancestry tests look at three different kinds of DNA: Y-DNA, mitochondrial DNA (also known as mtDNA) and autosomal DNA. Here’s how these three kinds of DNA are different.
Y-DNA: If you are a man, scientists will be able to look at your Y-DNA to determine how you may be related to others. This kind of DNA is passed from father to son through the Y chromosome and genetically remains mostly unchanged.
This makes Y-DNA extremely helpful in DNA tests to find ancestors because it can be used to track the genetics passed onto you from your father’s genetic line, that he received from his father, and so on.
Unfortunately, women don’t carry Y-DNA simply because they have two X chromosomes and no Y chromosomes, so many women who consider using ancestry DNA tests to research their family often will speak with a male family member such as a brother, father, or uncle about using their saliva or cheek swab sample.
Mitochondrial DNA (mtDNA): This kind of DNA is different from Y-DNA because everyone has it. Mitochondrial DNA is passed from mothers to children, regardless of sex, through the X chromosome. When it comes to having a DNA test to find ancestors, think of mtDNA as a test that traces the maternal line of your family tree.
Because everyone has mtDNA, anyone’s DNA can be analyzed for this kind of genetic information. But, it’s also important to know that even though everyone has this kind of genetic code inside of them, mtDNA can only be passed from women, meaning that a DNA test that analyzes mtDNA will not show information about your paternal DNA, only information about female ancestors.
Autosomal DNA: Of the three types of DNA, everyone has autosomal DNA, but this kind of genetic information has nothing to do with your gender. Autosomal DNA is the portion of DNA that includes your other chromosomes — those not related to whether you are male or female — and impacts individual traits that make you who you are.
When your autosomal DNA is analyzed by genetic scientists, they’ll compare your specific DNA sample to that of a database of collected, anonymous DNA samples that have also been submitted. When using a DNA test for half siblings or a DNA test for adoptees, for example, autosomal DNA can look at your DNA and that of other people to see if you share similar segments of DNA, and if those segments are so similar that you must be related.
Autosomal DNA is also what is used to determine your ethnic group, so if you’re looking to for DNA tests for Native American ancestry, or DNA tests for Jewish ancestry, for example, you’ll want to ensure that the test you select examines your autosomal DNA.
After submitting your DNA through an at-home DNA test, and having autosomal, mtDNA, or a Y-DNA analysis performed, your test results will be sent back to you. For most people using a DNA test to find ancestors, these results will be able to show ethnic groups that your DNA matches with, potential family member matches (and how much DNA you share), and other features.
What Can You Learn About Your Family From DNA Tests?
Based on the kind of DNA test you’re considering and the information you are looking for, DNA tests can potentially offer a wealth of information.
In general, if you choose to submit a DNA test to find ancestors, you can expect to find out more information about:
Your ethnicity: Many people who are unfamiliar with their family’s heritage are able to learn more about themselves and their ancestors by taking DNA tests. This can be especially helpful for some ethnic groups, such as African Americans, who have more difficulty tracing their family lineage because of minimal records and major historical events.
For example, DNA tests for Native American ancestry are popular because it allows many Native people to reconnect with lost tribal communities and family members. Additionally, DNA tests for Jewish ancestry have become popular because they can identify if you are Jewish, and even the line of Jewish descent your ancestors identified as (such as Ashkenazi, Sephardim, Levi, and Cohen).
Regional information and migration routes: Many ancestry DNA tests will show you regions that your ancestors may have lived. While it can be exciting to learn that your roots trace back to Italy, Spain, or another country, it can be a bit misleading.
That’s because modern DNA tests compare your genetic information to that of other living people who currently reside in other areas. That doesn’t mean your ancestors didn’t live in that region or weren’t a particular nationality; the important takeaway here is knowing that you share genetic similarities with people who currently reside in those regions.
With regional information, a DNA test to find ancestors can provide you with additional background on important events that happened in a region where your family once lived, which can help give clues to tracing your family’s story. Many DNA tests that specifically are used to help people trace their family history also offer ideas for how your ancestors may have migrated across the globe to where you are today.
DNA matches with potential family members: One of the most exciting parts of using a DNA test to find ancestors is that you can link up with current, living people who you are related to. This advancement in DNA genealogy is especially appealing to people who don’t know much about who they are, or who their families are.
Using DNA genealogy as a DNA test for adoptees, or as a DNA test for half siblings can especially help people identify their birth family or family members who they didn’t know existed.
Unexpected DNA results regarding relatives: As DNA testing becomes more and more popular, some family members are coming across unexpected, staggering results — specifically that family members are genetically unrelated, or related in ways that conflict with the family’s current organization. Many families who have chosen to have several loved ones take a DNA test have been shocked to find out that a family member was unrelated or adopted.
Whether considered fortunate or unfortunate, the popularity and access to DNA testing has allowed many families to unearth hidden family secrets. When deciding upon purchasing and submitting a DNA test, it is important to think about how the results could impact your relationships with family members on the off-chance that surprising results to come up.
How Can DNA Tests Tell Your Ethnicity?
Many DNA test kits say that they can tell you the ethnicity of you and your family.
While this use for DNA isn’t an exact science, it can be helpful for people who are taking DNA tests for Native American ancestry, or for people who come from ethnic groups that have a harder time tracing their family trees. DNA tests can provide this kind of information by comparing segments of your DNA to the DNA of known ethnic groups, and seeing how it compares.
This allows scientists to determine your ethnic makeup, which can be varied with many results. According to one of the largest genealogy DNA test companies, AncestryDNA, estimating your ethnic background is very much a work in progress and not an exact science, though genetic scientists are working to understand how DNA is passed through families so that future results are more accurate.
It’s important to know that as family tree DNA evolves, and more and more people submit their own DNA to find out more about themselves, it’s possible that your initial results can change. That’s because each DNA testing company uses their own database instead of sharing a DNA database from which everyone could pool results.
Because of this, each company has a proprietary approach to data analysis. As more people sign up, the company’s database of DNA grows, and previous samples are then compared to new samples that are sent in.
This constant reanalysis makes everyone’s results more accurate because it increases the pool of DNA for analysis. While these tweaks can seem annoying, this approach to fine tuning DNA data for ethnicities is actually more inclusive, because more people of different ethnic backgrounds can be represented.
So, what does this mean about the validity of your ethnicity results? Turns out that companies such as AncestryDNA say this helps improve your results, meaning that your ethnicity estimate isn’t necessarily wrong.
In some cases, you may begin to get newer information about specific regions that your ancestors are from, and for some people, that can mean having their results show DNA similarities with multiple countries to one country, or even more fine tuned down to one city.
On the flip side, some people find that as DNA data pools grow, their results drastically change. In this case, it’s important to remember that ethnicity is a combination of both race and culture, and if your family has celebrated cultural holidays and traditions for generations, family tree DNA test results shouldn’t mean you should stop.
While DNA is a great tool for understanding more about your family, it shouldn’t completely outweigh your family’s traditions, oral and written history, special activities, or other qualities that make your family unique.
Essentially, if you are highly interested in knowing your ethnic background and plan to use a genealogy or ancestry DNA test to find out more about your heritage, know that checking in regularly regarding data updates can help you feel most confident in the results.
How Accurate Are DNA Tests For Genealogy?
The jury is out on just how accurate DNA tests used for genealogy are.
When it comes to using a DNA test for half siblings, or a DNA test for adoptees, these tests can be very accurate at identifying relatives and birth families because of how much DNA you share with close family members. For example, parents and children and siblings share around 50 percent of their DNA, while other relatives such as grandparents and half siblings share about 25 percent of their DNA.
These percentages quickly drop for more distant relatives, meaning that tests that identify close family members are pretty accurate.
When it comes to accuracy of estimated ethnicity, it’s not so clear as to how accurate genealogy DNA tests are. Because DNA test companies use different databases and algorithms to determine where your family may have been from and what DNA constitutes a particular ethnicity, there can be large differences when it comes to analyzing one person’s DNA with different test kits.
This doesn’t mean any test is inaccurate, but that the results simply aren’t very precise and can vary based by company. In addition, DNA tests that focus on ethnic group makeup and share a percentage aren’t necessarily correct.
Upon receiving DNA results that show ethnicity estimates, many people question the accuracy of their DNA test because they see small percentages of DNA tracing back to African countries. Regardless of your perceived ethnicity, how you identify yourself to the world, or what your family history and traditions suggest, it is important to know that all people will have DNA test results with some form of African DNA.
That’s because genetic scientists believe all humans are descendants of an ancient human group that originated in African regions. Some ancestry DNA tests will automatically omit this small percentage of DNA from your results, but if you do see it, don’t be alarmed at your test’s validity.
What Is The Best DNA Test For Ancestry?
When it comes to selecting a DNA test to find ancestors, or a DNA test for living relatives such as siblings or birth family, selecting a test with a large database of DNA is very important.
This gives you a larger chance of linking up with other relatives who have also submitted DNA to the test company. In addition, if you’re looking to use your DNA results to help with your family tree research, you’ll want a test company that offers results alongside genealogical records and databases.
Some of the best DNA tests for ancestry and genealogy include:
- AncestryDNA: One of the most well-known family tree DNA testing companies, AncestryDNA is known its extensive DNA database. For this reason, many people choose to use AncestryDNA kits because they feel that they have higher chances of connecting with unknown family members. Plus, the company can help you construct your family tree with historical documents and DNA combined, making it a top pick for family historians.
- FamilyTreeDNA: Whether you’re looking for Y-DNA, mtDNA, or just general DNA tests, FamilyTreeDNA offers multiple options. FamilyTreeDNA claims to have the most comprehensive DNA database for family tree research, and after getting your results back, you’ll be able to explore your ethnicity estimates through a map. FamilyTreeDNA was one of the first companies to offer DNA services for genealogy purposes starting nearly 20 years ago.
- MyHeritage DNA: Like other genealogy sites, MyHeritage.com allows you to start a family tree and compile records from its research databases. It also offers DNA testing kits that can help pad out the information you’ve added to your family history. MyHeritage DNA combines family tree research with DNA matches to help you connect with unknown relatives.
- 23andMe: Another popular DNA test kit option, 23andMe can open the doors to more information about your estimated ethnicity, and where in the world your ancestors came from. However, 23andMe does not offer any genealogical information, such as census and immigration records, to help you compile your family tree. Still, this brand — which is known for its focus on the role between DNA and health — is a strong option if you’re not necessarily concerned about building a digital version of your family tree.
When it comes to selecting the best DNA test to find ancestors, consider asking yourself these questions that can help you make the best choice:
What kind of information am I looking for? If you’re looking specifically to match with other family historians or genealogists who are also submitting DNA tests, this kind of test kit could be most beneficial.
Still, if you’re looking more for data about your personal health and attributes, or considering genealogical health histories that use DNA to build out information about a family’s inherited health conditions, another kind of DNA test kit that is more focused on health and less on family history (such as 23andMe) may be a better fit.
How could this information possibly help me? You’ll need to understand what kind of information you’re looking for, and how it could help your genealogy research. If you strongly believe that family members and ancestors are of a certain ethnic group because of family traditions and oral history, but are struggling to piece together verification with historical documents, a DNA test may be a great tool at helping you compile your family tree.
Knowing ahead of time what your genealogy research goals are before selecting a test can help you pick the best option.
Am I willing to match with other anonymous DNA data and possibly connect to share genealogy and family history information? Before submitting your DNA sample, you’ll have a chance to opt-in or opt-out of genetic matching with other test takers. This means you’ll allow your DNA to be anonymously compared to the pool of genetic samples, and should it come up with a close match to another test taker, you would both be notified of being relatives.
If you don’t feel comfortable doing so, that’s okay, and many test companies will still provide you with some results, such as your estimated ethnic breakdown and estimated migration routes from your family’s origins to where they are today.
Can A DNA Test For Ancestry Help Find Relatives?
Many people who take DNA tests for Jewish ancestry, DNA tests for Native American ancestry, or DNA tests for other genealogical reasons have been able to identify relatives.
To open up the possibility of finding relatives through DNA tests for ancestry, you’ll want to be sure that your DNA matching option is turned on — something that you’ll have to opt into for security and privacy reasons. In the event that you do match up with relatives, your DNA test company will explain how close you are related, and will estimate what kind of family relationship you may have, such as being a cousin, niece or nephew, sibling, aunt or uncle, or parent.
From there, you’ll be able to communicate with that person and work towards finding out how precisely you are related.
Can DNA Tests Find Your Family Tree?
In some ways, DNA tests can help you pad out your family tree, and identify people who you are likely related to, but they can’t be used to create a family tree entirely.
Some people who take ancestry DNA tests may find that they don’t have any close matches, and therefore aren’t able to link up with close family members they didn’t know about. But, other people do have luck with family tree DNA kits.
The DNA matches they find can help them work with distant (or closer) family members to understand how they are related, and share family history information. DNA is a great tool in a genealogist or family historian’s kit, but it won’t do all the work of tracing your lineage.
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