However, there’s more to these genetic tests than meets the eye. We’ll explain the top 10 things you should know before you take an at-home DNA test.
DNA Tests Can Tell You about Your Ancestry
One of the most common reasons to use an at-home DNA test is to learn more about your ancestry. DNA tests are great for this, especially if you want to know about your ethnicity at the continental level. They can readily tell you whether your ancestors came from Europe, the Middle East, or Asia, for example.
However, at-home tests become less accurate if you want information about what specific country your ancestors are from. For example, if you want to know just how much Italian heritage you have, you might find that an at-home test doesn’t provide the level of detail you’re after.
There Are 3 Different Types of DNA Tests
Another important thing to know about using DNA tests to find out about your ancestry is that there are 3 different types of tests.
Autosomal DNA tests sequence genes that were passed down from both your parents. These tests are the most common, as they tell you about your overall lineage without distinguishing between your mother’s and father’s ancestry. Autosomal DNA tests typically provide reliable information going back 4-5 generations
Mitochondrial DNA tests, or mtDNA tests, only examine genes passed down from your mother. So they can trace back your ancestry only on your mother’s side of the family. mtDNA tests can provide information going back 8-10 generations, but they don’t offer much information about family structure.
Y DNA tests only look at genes passed down from your father and can only be used to trace ancestry on your father’s side of the family. Y DNA tests are only available for men since women don’t have a Y chromosome. Like mtDNA tests, Y DNA tests provide information about the past 8-10 generations.
An Ancestry Testing Company is Only as Good as Its Database
To provide clear and reliable information about your ancestry, DNA testing companies rely on databases of genetic information. These databases usually include publicly available genetic information as well as genetic data from a company’s other users.
The bigger and more comprehensive a testing service’s database, the better. With a larger genetic database, a company can more accurately trace your genes to a specific ethnic group or help you find past relatives.
That’s part of the reason why it makes a lot of sense to stick with popular ancestry testing companies like MyHeritage and LivingDNA. These companies have already had millions of users test their ancestry and contribute genetic information. This means you get access to more detailed information about your own ancestry.
DNA Test Results Vary
One thing that might surprise you is that at-home DNA test results can vary widely. This doesn’t have anything to do with the quality of the test kit or the sequencing process. Rather, it’s because different DNA testing services sequence different genes.
As a result, one DNA test might reveal that you’re 30% Irish, 25% Eastern European, and 45% East Asian. Another DNA test from a different company might look at an alternative set of genes and determine that you’re 50% Irish and 50% East Asian. It’s not that one test is right or wrong—they’re just exploring slightly different parts of your genome and coming up with different clues about your ancestry as a result.
In addition, analyzing your DNA sequences against different databases can yield slightly different results. If you’re not getting the ancestry results you expected from your testing provider, you can try uploading your DNA to a third-party database to reanalyze it.
DNA Tests Provide Information about Health Risks
DNA tests can also provide information about important health risks. There are at-home DNA tests for several hereditary cancers, including breast, ovarian, and prostate cancer. There are also tests for genes linked to cardiovascular disease and Alzheimer’s.
These tests can be useful, especially if you have a family history of these conditions. They can also alert you to potential future medical conditions so that you can take preventative steps now.
However, at-home DNA tests aren’t a replacement for a complete evaluation by a medical professional. Remember that they only look at your genes, not what’s actually happening in your body.
Your DNA Doesn’t Predict Your Future
Even if an at-home DNA test suggests that you are at risk for a specific cancer or a disease like Alzheimer’s, it’s important to keep in mind that this isn’t a prediction of your future health. There are thousands of genes related to conditions like breast cancer, and most genetic tests only look at a few of the most common.
In addition, many diseases linked to genetics depend on more than just your genes. Alzheimer’s, for example, is thought to depend as much on environmental conditions and on how active you keep your brain as you age as it does on your genetics.
So, if an at-home DNA test suggests you may be at risk for a specific condition, interpret your genes as one of many risk factors rather than as determinants of the future.
You May Need Help Interpreting Your Results
Receiving details about your genes can be confusing, or even overwhelming. After all, most people don’t have a degree in molecular biology and scientists themselves are still figuring out the limits of what our DNA sequences can tell us.
So, you might need help interpreting your results. Many genetic testing services offer analysis portals where you can dig deeper into your ancestry or even find close relatives. They may also offer more information about health-related genes and what they mean.
In addition, there are a number of third-party databases where you can upload your DNA sequencing results. These provide a different look at your ancestry and enable you to combine sequencing results from several different at-home tests.
Be Prepared for Surprises
DNA tests don’t always give you the results you expect. Many people find out for the first time that one of their parents isn’t actually their biological parent on the day they get their test results back. It’s also relatively common for people to find close relatives, including cousins and half-siblings, that they didn’t know they had.
Before you take a test, it’s worth considering what surprises like these might mean for you.
Privacy Rules Vary by Testing Provider
Privacy rules around at-home DNA test results are far from uniform. Many testing companies promise not to share your test results, while others may use your DNA sequences for research or share them with healthcare providers. In addition, most testing providers add your DNA anonymously to the company’s database and there may not be an option to opt out.
DNA Testing Can Impact Your Life Insurance Policy
Importantly, at-home DNA test results cannot impact your health insurance or employment prospects. No matter what you find out from your DNA, the Genetic Information Nondiscrimination Act of 2008 forbids discrimination based on your genes.
However, that federal law doesn’t apply to life insurance, long-term care insurance, or disability insurance. These types of insurance providers can charge higher premiums or even decline to issue you a policy if your genes suggest you’re at high risk of particular diseases.
For now, few life insurance companies ask applicants for information about DNA test results. That could change in the future, though, and your DNA test results could end up raising or lowering your life insurance premiums.
At-home DNA tests can tell you a lot about your ancestry, your family, and your health risks. Before you dive into taking a test, however, it’s important to think about how to interpret the results you get and what they actually mean.
For ancestry tests, your results can vary based on the type of test you take and what set of genes a service sequences. For health-related tests, keep in mind that most DNA testing providers only sequence a tiny subset of genes related to conditions like cancer and that your genes are just one risk factor out of many.
Ready to take a DNA test? Check out our reviews to find the best DNA tests for ancestry, health, and more!