For years, if you wanted to get any health-related information from a DNA test, your only good choice was 23andMe. 23andMe was the first company (in 2017) to receive FDA approval to market genetic risk information for certain conditions. But the landscape of genetic health testing has changed dramatically in recent years and 23andMe is no longer alone atop the mountain.
When it comes to DNA health testing, many companies now compete for your business. This growing and increasingly competitive field of providers creates the potential for a better testing experience but also poses a growing challenge: how to find the best DNA health testing kit.
Our experts have thoroughly tested the services of major and minor companies in the DNA testing arena. Here in this guide, we will break down the pros, cons, and all considerations to help you decide which health DNA test is best for you.
Summary of our top recommended DNA tests for health:
- Best all-around: Toolbox Genomics
- Best for carrier screening: Nebula Genomics
- Best for nutrition: InsideTracker
- Best for fitness: InsideTracker
- Best for cellular aging: Toolbox Genomics
- Best for health plus ancestry: Nebula Genomics
- Best for privacy: Nebula Genomics
- Best for accuracy: Nebula Genomics
Toolbox Genomics’ combination test puts you in a position to learn a lot about your health and also take actions aimed at improving it.
Gaining insights about both your genetics and epigenetics gives you a deeper understanding and positions you to take action. For best results, we recommend investing in the company’s Epigenetics Subscription to retest in a year.
DNA health tests can tell you quite a bit about certain aspects of your genetic health, ranging from serious to fun. Here are some of the specific areas that you can learn about:
- Genetic health risk
- Carrier screening
- Wellness and health traits
- Nutrition and dietary intolerances
- Cellular aging
When you take DNA tests for health purposes, keep in mind that genetics plays a role but is part of a broader picture – a fact that also shapes our top choices for 2020.
- Why you should trust us
- The best all-around testing for health and wellness
- Nutrition and fitness testing
- Carrier screening
- Cellular aging and epigenetics
- Are DNA health tests accurate?
- Privacy considerations with DNA health testing
- How we choose our recommendations
- How DNA tests work
- DNA health testing and ancestry testing
Innerbody Research recently celebrated its 20th anniversary online. Over the past two decades, we have helped tens of millions of readers make more informed decisions involving staying healthy and living healthier lifestyles.
Like all medical-related content on this website, this guide was thoroughly vetted by one or more members of our Medical Review Board for medical accuracy. Additionally, we extensively analyze each health-related service we review. We evaluate the entire customer experience from sign-up to use of the product or service, and then offer unbiased, marketing-jargon-free analysis based on the latest scientific evidence and medical standards.
Our testing team has purchased and compared hundreds of genetic tests to date, and we are constantly updating our reviews based on the latest test advances. During testing for this guide, dozens of companies rose above the rest, but among them we selected only the best in our estimation for the situations or considerations described in the guide.
Here’s a handy chart with top-level details about companies whose tests impressed us most.
|DNA health||Epigenetics||Ancestry||Whole-genome sequencing||Test type|
|Toolbox Genomics||At-home, saliva|
|Nebula Genomics||At-home, swab or saliva|
|InsideTracker||in-lab and at-home, blood and swab|
|TeloYears||At-home, blood droplet|
|Living DNA||At-home, swab|
It’s actually quite difficult to select the best all-around DNA test for health and wellness in 2020 because what’s best for you really depends on your goals. We organize this guide largely based on that fact. Genetic health testing is truly multifaceted and what’s best for one person may be the worst choice for someone else.
But, in making our choice, we identified healthy balances in a multitude of factors including, among others:
- Testing accuracy
- Abundance of data
- Ability to place genetic insights into a broader picture
- How actionable the insights can be
- Clarity of health reporting
This process leads us to recommend a test that we believe would be of most value to the broadest group of people – even with the recognition that this group is likely a slim plurality rather than a majority of people.
As our research team conducted its analyses, we came to the conclusion that a good amount of value to a customer comes with the ability to turn health insights into actions that lead to improvement. When people seek genetic health testing, they definitely want information. But beyond seeking information strictly for the sake of having information, most people want to do something with it. If planning to have children, people want to know their carrier status for various genetic health conditions. If trying to live healthier lives, people want to know not only what they inherited, but also how well they’re managing in life with the genes they inherited.
Our all-around choice for 2020
Toolbox Genomics, as a company, focuses entirely on genetic health testing and has a history of providing tests to healthcare professionals who seek high-quality testing for their patients. You can now buy them directly, and taking these tests is as simple as spitting into a tube at home.
The company offers a genetic health testing pathway that not only gives health insights related to the DNA you inherit, but also provides insights into how your lifestyle is impacting your health at a cellular level. Toolbox Genomics’ Epigenetics + DNA Test reveals valuable information about your genome AND your epigenome (which is a fancy term to describe all of the chemicals that are shaped by your lifestyle and affect your genetic expression).
When you subscribe to retest at a frequency of your choosing (3, 6, or 12 months), your test price reduces. You pay a monthly fee, but we believe the cost is well worth what you learn:
- Are you genetically predisposed to certain health risks and attributes?
- How well are you aging and how does this affect your vision, hearing, memory, inflammatory processes, and more?
- Are the actions that you take to improve your wellbeing having a positive effect on your health at this cellular level?
With its DNA and epigenetics testing, Toolbox Genomics gives you the health information and tools that you can use to make positive changes in your life. The company transcends DNA testing to provide a bigger picture of health insights you can use.
To learn more, visit our full Toolbox Genomics review.
Close runner-up: Nebula Genomics
For a pure focus on DNA health testing, as opposed to epigenetics, we’re confident you will be very well served by investing in Nebula Genomics’ 30x Whole-Genome Sequencing. You’ll notice we have pretty high praise for Nebula Genomics throughout this guide, and for good reason. Based on our thorough testing and comparative analyses, Nebula Genomics excels in many ways.
Nebula Genomics’ DNA test sequences 100% of your genetic code, which means maximum data for you. Its tools effectively help you make the most of it.
The company offers this whole-genome sequencing test for less money than competitors, making it a tremendous value. Recommended for its scope and the for exploratory tools at your disposal after testing.
As a company – like the other companies we recommend in this guide – Nebula Genomics is dedicated to offering health insights only as supported by solid, reputable scientific research. But Nebula Genomics sequences your entire genome for the lowest price available and makes it very easy to gain all of the health insights you can from your data. To put this into perspective, mainstream DNA testing companies will decode about 0.02% of your genetic code. (And as a bonus, you can benefit from the company’s partnership with Family Tree DNA to learn about your ancestry.)
The company’s dedication to privacy is also, frankly, unmatched. Nebula Genomics continues to lead in genetic data privacy and research.
They narrowly missed being our overall top choice only because we feel customers have so much to gain by including epigenetics testing in their pursuits. Nebula Genomics doesn’t offer this type of testing right now, but its whole-genome sequencing service is so excellent that the separation between these two companies in our estimation is razor-thin. You can’t go wrong either way. Your decision should be based only on your own priorities in testing.
You can learn more by visiting our full Nebula Genomics review.
A quick rundown of our favorite tests
Here is a quick cheat-sheet of specific tests that impressed us for different reasons. (In the case of InsideTracker, our recommendation is to combine the two tests listed here. However, if you’re on a tighter budget, the company offers multiple blood biomarker tests that are less expensive than the “Ultimate” test while still providing valuable nutritional and fitness insights.)
|Price (with discounts)||Company||DNA health insights||Complementary health insights||Top strengths|
|Epigenetics + DNA Test||$249||Toolbox Genomics||All-around, actionable insight|
|30x Whole-Genome Sequencing||$299||Nebula Genomics||Most data, accuracy, privacy|
|DNA Kit||$189||InsideTracker||Nutrition & Fitness|
|Ultimate Blood Test||$442||InsideTracker||Nutrition & Fitness|
|TeloYears||$89||TeloYears||Epigenetics, actionable insight|
|Ultimate Genome Sequencing||$399||Sequencing.com||Most data, privacy|
|Health + Ancestry||$199||23andMe||Genealogy with health|
Some “wellness” areas are more popular than others, and nutrition and fitness are perennially among the most popular. Tests in these two areas aim to go beyond simply giving you nice-to-know information. Instead, they give you actionable recommendations that will enable you to live a more healthy lifestyle.
When you combine InsideTracker’s DNA Kit with a blood test for additional biomarkers, you’re well positioned to gain the most nutrition and fitness insights.
InsideTracker’s tests and tools are designed to satisfy everyone from professional athletes to the person who just wants to get in better shape. Putting genetic health insights in broader context is the best way to improve nutrition and fitness.
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In a nutshell, DNA tests for nutritional health look at specific gene variants that are thought to be associated with particular traits such as metabolism, muscle tissue type, gluten sensitivity, and nutrient absorption. DNA tests of this kind can be motivating and fun, as long as you:
Take the resulting recommendations with a grain of salt
Keep in mind that lifestyle and environmental factors also weigh heavily in most outcomes.
Consult a professional nutritionist before making any drastic diet changes, these tests can be motivating and fun.
But we assume you’re here not just for fun. You want to know which DNA health tests will deliver the most insight into your personal nutritional needs.
Best for nutrition and/or fitness: InsideTracker
If your goal is DNA health testing to understand your own nutritional and fitness needs as an organism and then take steps to achieve optimal success, we think InsideTracker has the best testing approach. For the most impressive results, we recommend the Ultimate Blood Test combined with the DNA Test to provide the most comprehensive and actionable insights.
InsideTracker not only dedicates itself to providing insights using only the most rigorous scientific research, but it’s also refreshingly transparent about that science. And because genetics is only part of the picture of health and nutritional needs, the DNA health testing approach you can take with InsideTracker reflects a solid, mature scientific standpoint. When it comes to nutrition and fitness, you can learn most from DNA health testing when you don’t examine DNA data in a vacuum.
With InsideTracker, you can and should take advantage of simultaneous DNA testing and blood testing for a multitude of other biomarkers. Toolbox Genomics offers this dual-testing approach in a convenient set of package options. Meanwhile, the company uses an impressive, proprietary algorithm called SegterraX to process and combine:
- All of your DNA and blood test data
- Your personal information about height, weight, gender, and ethnicity
- Lifestyle information that you provide in areas such as fitness, diet, and mental health
- Truly massive amounts of data from all of the scientific studies and databases it finds sufficient cause to trust
Computer scientists much smarter than us devised this algorithm (likely thanks to the company’s roots at Harvard, MIT, and Tufts).
Testing with InsideTracker isn’t the cheapest path – whichever blood biomarkers test you choose to add to your DNA health test, you’ll pay hundreds of dollars. But you can take advantage of our promo code (INNERBODY25) to take 25% off of your price, making our top recommended combination of tests (the Ultimate Blood Test and DNA Test) cost $629. With this package, we believe you’ll gain the most comprehensive and valuable insights about your nutritional needs. (With less comprehensive blood testing options, you can lower the cost.)
Additionally, InsideTracker gives you the tools to help take action with the information you gain.
- Like the best nutrition and fitness apps, you can easily set goals and track your progress.
- InsideTracker’s fitness and nutritional suggestions are grounded in the reality that tastes and abilities vary, letting you take action in the ways you know you can sustain.
- InsideTracker offers elite dashboard support suitable for coaches and athletes alike, satisfying the needs of pros, aspiring pros, and the rest of us who want to reach peak performance.
InsideTracker’s insights are also uniquely actionable because the company transparently grades the suggestions based on the extent to which they’ve been confirmed in scientific studies. InsideTracker does all of this legwork for you with transparency, allowing you to prioritize the nutritional and fitness suggestions that research indicates are likeliest to help you in your goals.
This is not a fully at-home test provider. While the DNA test kit is a straightforward at-home cheek swab test, your blood test will instead be administered at one of InsideTracker’s over 2,000 top-notch lab partners across the United States. As long as you’re willing to test in a lab, this dual approach is our top pick.
You can learn more about InsideTracker and all of its testing options at our full InsideTracker review.
Runner-up for nutrition and fitness: Vitagene
If the prices at InsideTracker are unaffordable or you’d prefer testing at home, our runner-up suggestion for nutrition and fitness is Vitagene. Though it doesn’t enable the same broader contextual information of a complementary blood test, Vitagene has its own impressive algorithm that processes your genetic data alongside all of the best scientific evidence in order to provide you with insights. Vitagene doesn’t match InsideTracker for thoroughness or transparency, but it provides valuable insights about diet, workouts, and supplementary nutritional needs based on your genetic data. (As a bonus, you’ll also gain some insight into your ancestry in the process.)
The price of the test we’d recommend is only $108 (the Premium Test). For $269, Vitagene adds in a 90-day supply of supplements that your test results indicate would benefit you. For more information about the company, visit our full review of Vitagene.
Honorable mention for nutrition: TeloYears
On the surface, TeloYears might seem like an unlikely runner-up for genetic health testing focused on nutrition. But we believe that many people with this goal could benefit from what the company has to offer.
- If you can’t test in a lab or prefer testing at home for convenience, you can do this with TeloYears.
- If you can’t afford the price of InsideTracker, TeloYears offers a 6-month program starting at $210 that combines before-and-after testing with carefully formulated nutritional supplementation.
- Strict DNA testing for nutritional needs is not as firmly grounded as other aspects of health and wellness, but epigenetics is a different situation and its test results are truly actionable.
TeloYears offers comparably low-priced epigenetics testing that focuses on Telomere length (a measurement some scientists now call “the new cholesterol” because of its association with heart disease risk. And TeloYears conveniently provides a program of nutritional supplementation to improve your biological age, which it will measure for you with follow-up testing. To learn more, visit our full TeloYears review.
For many people, carrier status is the main reason for buying a DNA health test. Do you carry a genetic variant for a health condition?
Carrier screening is a type of genetic testing that can tell you whether you carry a gene variant associated with certain genetic disorders. Most of the time, these variants will not affect you directly, but you may pass them on to your children. Examples of diseases that can be passed on in this way include cystic fibrosis, sickle cell anemia, and hereditary hearing loss.
Most commonly, if both parents are carriers for a certain disease-causing variant, there will be a 25% chance that their child will be affected by the disease. Taking genetic screening tests can allow couples to take steps to minimize the chances that their children will inherit a disorder, or allow them to plan for the future, often with the help of a genetic counselor or their healthcare provider.
There was a time when 23andMe was the go-to provider for this kind of information. But your options have greatly expanded and, based on our testing, we believe you’ll be better served with different genetic testing that helps you unlock potentially more of this important information.
Best for carrier screening DNA health testing: Nebula Genomics
Sequencing your whole genome with Nebula Genomics positions you to look for more gene variants than with major DNA testing companies.
Nebula Genomics gives you the ability to check your entire genetic code for any gene variant that’s ever been studied. You pay a bit more for this comprehensive ability, but it’s a fantastic value and less expensive than other whole-genome options.
Our top choice for DNA health testing to learn about carrier status is Nebula Genomics. Here’s why:
Volume of data. Other prominent testing companies like 23andMe decode about 0.02% of your DNA. Nebula Genomics decodes 100% of it.
Tools to search for genetic variants easily. Once you have 100% of your genetic data, Nebula Genomics not only provides weekly updates and information about the latest scientific understanding of genetic variants, but also gives access to search tools that easily allow you to check your fully decoded genetic data for any genetic variant that has ever been studied. This is much more expansive and powerful than being given information about a specific, limited set of genetic variants like other companies do.
Value. Nebula Genomics sequences your entire genome for a lower price than any other company.
Privacy. In our experience, no company puts a bigger emphasis on protecting your genetic data than Nebula Genomics.
We’re very impressed by Nebula Genomics, a company founded by the genetics pioneer and Harvard professor George Church. The company has been at the forefront of both personalized genomics and gene-editing research and leads the industry in its simultaneous pursuit of unparalleled data privacy and groundbreaking research.
It is now possible to learn about how well your cells are aging using genetic health testing, right from the comfort of home. To understand this capability, we have to recognize the difference between genetics and epigenetics. These are confusing concepts so let’s break it down a bit.
What is epigenetics?
Epigenetics literally means “above genetics” or “on top of genetics”. While DNA is your genetic code – an inherited blueprint for how your body functions – epigenetics is the term scientists use for all of the chemical compounds that mark your genetic code throughout life and affect your genetic expression. Some people suggest thinking of your genetic code as a cookbook filled with recipes. In this case, epigenetics will be all of the little notes and highlights scribbled onto them, filling the margins over time. Epigenetics is how gene expression can change even without any changes to the underlying genetic code.
Who is making those scribbles and highlights? Believe it or not, you are – at least partly. Some of our epigenetics can be inherited, but your lifestyle choices – how you sleep, eat, exercise, and cope with stress – and various environmental factors contribute to your epigenetics as well. As you explore what genetic testing can reveal about health, it’s valuable to consider not only your genome but also your epigenome.
This is particularly important when considering what actions you might take based on results.
Our choice for cellular aging and epigenetics: Toolbox Genomics
Sometimes we can convince and motivate ourselves to make vitally important changes only after making what feels like a considerable investment. If you buy an old, used car, you might not feel as motivated to maintain it as if you had bought a luxurious, new car that cost more money.
Toolbox Genomics’ Epigenetics + DNA Test is that new car. If you buy this test and make the commitment to retest in a year via a subscription (our recommendation), we believe you’ll be set to develop the best understanding of your cellular aging and the best chance of improving it. Yes, it’s not cheap; this powerful test costs $249 if you subscribe, and you then spend a little over $200 more for the subscription to retest after a year. Though this is an investment, the service is a tremendous value for what you get from it: actionable insights for you to make healthy life improvements and then measure their effect.
Toolbox Genomics’ epigenetics test and subscription help you understand your genetic health and biological age.
The company doesn’t just give you one age value, but instead looks at your epigenetics with a focus on vision, hearing, memory, inflammation, and more. You not only gain insights, but you’re also equipped to take action.
If you’re somebody who frequently tells yourself, “I know I could be living healthier,” and you need that extra nudge to commit to it, then Toolbox Genomics will put you in a position to take action. After a year, you’ll have the gratification of seeing the results of your efforts.
Close runner-up: TeloYears
TeloYears is an outstanding company and a pioneer of at-home genetic health testing focused on learning about the condition of your telomeres. Telomeres are cap structures that protect the ends of our chromosomes from degradation. Your telomeres naturally wear down and shorten as you age; each time a cell divides and DNA replicates itself, telomeres get a little shorter. Eventually, telomeres are so short that the cell cannot properly divide.
With TeloYears, you can take a test at a very low price in order to gain a very important measurement: your average telomere length.
Many scientists consider telomere length to be "the new cholesterol" because of its associations with the risk of heart disease. TeloYears provides vital epigenetic health insights using a very affordable test.
Scientific evidence shows that other factors within our control can affect our telomere length positively and negatively, including stress management, diet, exercise, and sleep quality, to name a few. This is a significant window into epigenetics affecting your health at the cellular level.
By measuring the length of your telomeres and comparing this result to others of your age and sex, it’s possible to estimate how well you appear to be aging compared to others of your demographic. TeloYears’ health test doesn’t provide insights broken down by vision, hearing, memory, or other granular ways. Instead, it provides:
- You overall biological age
- The opportunity to track your improved biological age with repeat testing as you take action
- A valuable distillation of decades of telomere and aging science in one understandable learning resource
What makes TeloYears so appealing is that it yields valuable insight for a lower price. If you’re on a tight budget but want to learn about your cellular aging broadly, you can trust this company. TeloYears has been at the forefront of at-home testing for cellular age, helping people understand how telomere length is a uniquely valuable measurement in our understanding of biological age.
The TeloYears test costs only $89, making repeat testing much easier for many of us. Not only that, but the company deeply discounts a before-and-after testing experience if you couple it with a subscription for longevity-promoting supplements sold by TeloYears. The strategy is to demonstrate to you that better nutrition can fundamentally improve your health and longevity at the cellular level – something TeloYears’ tests empower you to measure.
A 6-month subscription to supplementation, along with before-and-after testing, totals only $210 – a little less than half of what you would pay for the yearlong Toolbox Genomics testing subscription. You won’t get as granular of a breakdown of your biological aging, but you’ll get high value and actionable insight for less money.
When you test with reputable companies whose labs are certified to meet high standards, DNA health testing is highly accurate. This is true of all of the tests recommended in this guide. Even within this group, differences in accuracy can exist, but we may be considering a difference of 98% accuracy vs. 100% accuracy, for instance.
Which DNA test is the most accurate?
Among these highly accurate tests, Nebula Genomics edges out the competition with its 30x Whole-Genome Sequencing test ($299). This test not only sequences 100% of your genetic code, but it also reads each letter of your DNA 30 times on average, virtually ensuring total accuracy and thoroughness.
A note of caution
With DNA Health testing, once you narrow down your choices to include only top-notch tests as we have done in this guide, testing accuracy isn’t so much the concern as is the tendency to jump to health conclusions based on test results. The testing may be 100% accurate, but conclusions we may independently draw from the testing can be far less reliable. When you invest in genetic health testing, be careful about the possibility of taking accurate results and turning them into inaccurate conclusions. Testing with our top providers can help to prevent this risk because the companies provide valuable, science-based materials and tools to help you understand your results.
Interpreting your test results
There is a lot to consider both before and after undertaking a health DNA test. If you’re planning on taking health DNA tests, it can be valuable to get in touch with a genetic counselor beforehand to discuss your expectations regarding the test, whether you may be distressed by the resulting information, and whether the benefits of learning such information outweigh the drawbacks. Genetic counselors are healthcare professionals with special training in the interpretation of these kinds of reports. Consultation in advance is of course optional, and many customers don’t feel the need to do it.
However, it’s very important to discuss any worrying or alarming DNA health test results with a genetic counselor or healthcare provider, rather than trying to interpret the risk information yourself. Even if the test does not recognize any variants for a particular illness in your genome, this doesn’t necessarily mean you are not at risk of, or a carrier of, that disease variant. Not all variants for these illnesses have been identified yet. (Our selection of providers in this guide will all provide valuable information about this in the test reports themselves.)
If you do test positive for a particular disease risk variant or carrier variant for some specific illnesses, there are a variety of options you might consider to effectively minimize your risk and that of your children, and so you should share your results with your doctor.
Our top pick, Toolbox Genomics, makes it very easy to share your results with your healthcare provider directly within the app itself.
Your genetic data is the most personal information you possess, and privacy is an important consideration when deciding which DNA testing provider to use. All DNA testing companies will have comprehensive privacy statements, and these are the best places to start when evaluating different providers. Common privacy considerations include:
- Whether you want your sample discarded or stored after analysis by the lab
- Which health reports you would like to opt into or out of
- The parties with whom you’d permit a company to share your information
- Whether or not you consent to the use of your DNA results for scientific research purposes
Most companies go to great lengths to ensure confidentiality, though their practices do vary. If you’re concerned about privacy, some research on the company website is advisable before committing to a particular test provider. You may also want to take a look at our popular guide: DNA Testing Privacy: 5 Recommendations for New Test Takers.
Controlling your data
Control of your data is an important consideration for some DNA testing customers. When it comes to control of your data for privacy purposes, the central questions are:
- Can you destroy your test sample if you want to do so?
- Can you destroy your data if you want to do so?
Here is a comparative chart with conclusions based on our testing and analysis.
|Easily delete your data||Easily destroy your sample|
Which company is most dedicated to protecting your privacy?
In 2020, we are most impressed by two companies when it comes to privacy protection:
- Nebula Genomics
Sequencing.com will never sell your data and won’t share it with anyone unless you permit it. You can also easily delete all of your genetic data at any time. Sequencing.com’s policies are transparent and trustworthy and protect your genetic data with the same security measures as a bank uses to protect your financial data. Learn more about the company with our full Sequencing.com review.
However, Nebula Genomics’ commitment to privacy is the most impressive of any DNA testing company we have tested.
- The company was the first to allow anonymous DNA testing, which you’d never want to do if you’re trying to find relatives, of course, but is very useful for people who want none of their identifying information associated with their DNA data.
- You can delete all of your data at any time.
- You have total control over the anonymized sharing of any data with researchers.
- Nebula Genomics is developing groundbreaking blockchain-based technologies to enable total privacy even for those who wish to help advance scientific study by sharing data.
With its dedication to privacy and innovative thinking, Nebula Genomics stands out from the competition.
We customize our evaluation criteria depending on the type and nature of the health-related test. For DNA test kits, we have five areas that we use to evaluate and ultimately form our recommended tests. They are:
Testing Technology: Does the testing company use the latest and most accurate testing technologies available? How frequently does the company update its gene chips to reflect the latest scientific advances and new links between DNA and disease, genes, and base pairs?
Results Presentation: How clearly are the test results presented? Are the results easy to understand? For those who want it, how much scientific detail do the results offer?
Value: Are you getting your money’s worth? Will you have (free) access to new results as the testing company updates its gene chips in response to new scientific advances? Are there any hidden costs or charges (shipping, etc.)?
Customer Support: If you have any issues with your test, how well does the testing company respond? How well does it answer questions you may have regarding the test results?
DNA is the genetic code that governs the functioning of our cells and essentially determines every biological aspect of who we are. You can think of it as a kind of blueprint that controls the way your body works, which is passed down through the generations in the form of sequences of code called genes. All humans share over 99.5% of our DNA with one another, but it is the genes making up the 0.5% difference that account for all the diversity we see among individuals. These gene differences are called “variants,” and while most gene variants are neutral, or account for the normal variation among us all, some can cause serious diseases.
DNA testing involves providing a sample of your DNA (usually in the form of a saliva sample) which is sent to a lab for analysis. Using the extensive databases and associated research, testing companies can predict your risk of developing certain diseases based on what gene variants are present in your code. You’ll receive comprehensive reports outlining your risk factors for each disease, along with your carrier status and additional information explaining how to interpret the results.
The concepts of DNA, genes and chromosomes can become quite confusing. For those who want to get a better understanding and demystify the DNA testing process, let’s go a bit deeper.
DNA, genes and chromosomes
Our bodies are made up of trillions of cells, the basic units of life. Within the nucleus and mitochondria of each cell, there is genetic material called DNA (deoxyribonucleic acid), that controls almost every aspect of how a cell functions. DNA is often referred to as the “blueprint” of life because as cells multiply, their DNA is the informational code that directs the development of new cells (similar to how building blueprints direct the construction of new buildings). Specific areas of DNA molecules contain sequences of code that determine traits that are passed down from parent to offspring, and these are called genes.
Chromosomes are long strands of DNA that contain many genes. With rare exceptions, humans have 46 chromosomes arranged in 23 pairs, where one chromosome from each pair is inherited from your mother, and the other from your father—this is where the testing company 23andMe gets its name. Hopefully our diagram illustrates how all these terms fit together.
DNA is a double-stranded molecule in the shape of a double-helix composed of a sugar-phosphate backbone onto which are attached four different bases: adenine, thymine, cytosine, and guanine. The sugar and phosphate form the supporting DNA strands (shown in grey) and the bases form the inside pairs (shown in color). How the four bases are arranged spells out the language known as the genetic code, which determines who we are. Most genes can be thought of as recipes for making specific proteins. These recipes are replicated and passed down from parent to child, generation after generation.
The copying of the recipes, however, is not always perfect. Sometimes copy errors are made, and these errors are called mutations. Some mutations are harmful and can cause severe disease, but many are neutral and contribute to the natural genetic variation we find among individuals. If such a mutation is passed down through the generations and becomes prevalent to a certain degree in a population, it becomes known as a single nucleotide polymorphism (SNP, pronounced: “snip”). Of the over 3 billion base pairs in the human genome, around 10 million are SNPs. Essentially, this means that we share over 99.5% of our DNA; the 0.5% difference caused by accumulations of SNPs accounts for most of the variation between you and everyone else on the planet. Amazing!
As SNPs are heritable and vary between populations, comparing the SNPs that pop up frequently in one group of people vs another is how we can make educated guesses about where your ancestors came from and what physical traits you are likely to have. DNA testing is simply the process of extracting your genetic code, focusing on what SNPs are present in your code, and telling you what traits, ethnicity, or disease risks are currently thought to be associated with those particular markers.
The DNA collection process
Submitting your DNA to a DNA test provider such as 23andMe or AncestryDNA is incredibly simple. You just have to submit your saliva or a swab from your cheek and the lab does the rest. The first step in the extraction process at the lab is to isolate the DNA so that it is in a purer form. Then, the DNA is placed into a machine where it is analyzed by a DNA genotyping chip. These chips target specific genetic markers, usually short DNA sequences surrounding SNPs. Once the sample is genotyped, the information is loaded into the data system and you are sent a report outlining what your DNA says about you.
Different types of DNA
One last thing that is helpful to understand is that the DNA in our bodies can be grouped into several different categories. We will cover here the three most common categories used for direct-to-consumer (DTC) DNA testing.
We mentioned earlier that almost all humans have 23 pairs of chromosomes in the nucleus of most of their cells. Of these 23 pairs, 22 of them are made up of what we call Autosomal DNA. This means that the DNA contained on these 22 pairs of chromosomes is not integral to determining the sex of the individual. One copy of each of these chromosomes is inherited from one’s father and the other from one’s mother.
Why take this test and what are the limitations? Autosomal DNA forms the basis for most of the information we can learn from genetic testing, as it covers 22 of our 23 chromosome pairs, and can provide information about traits, ethnicity, ancestry and disease susceptibility/wellness. Autosomal DNA is inherited from both parents, and both men and women can have their autosomal DNA tested. Many genetic testing service providers focus solely on testing autosomal DNA, and it is by far the most common type of DNA analysis.
Y-chromosomal DNA (or Y-DNA/yDNA)
The “23rd pair of chromosomes” is unlike the other 22 and is often referred to as the sex chromosome pair. This pair determines whether you are genetically male or female. In almost all cases, a person inherits an ‘X’ chromosome from their mother, and either an ‘X’ or a ‘Y’ from their father (there are rare genetic disorders where we see other combinations). If your sex chromosomes are ‘XX’, you are genetically female, while if they are ‘XY’, you are male. Since only males have a Y-chromosome, this chromosome and its associated y-DNA is exclusively passed on from father to son.
Why take this test and what are the limitations? Y-chromosomal DNA testing is only available to men (as women do not have a Y-chromosome) and can allow male customers to gain great insight into the genetic ancestry of their fathers. Y-DNA is particularly useful for ancestral genetic testing because it does not undergo a rearranging process called recombination, unlike the other chromosomes, which are reshuffled and rearranged between each generation.
Women: do not despair! If a close male relative such as your father, brother, paternal uncle, or paternal male cousin were to have his genome tested, you can predict your own paternal lineage results from his reports.
Mitochondrial DNA (mtDNA)
Mitochondrial DNA is very unusual, as it comes not from the cell’s nucleus, but rather the cell’s energy-producing “factories” called the mitochondria. mtDNA is circular in shape and is only passed down from mother to child. Male children carry their mother’s mtDNA, but they do not pass it on to their children, who instead inherit it from their mother.
Why take this test and what are the limitations? Mitochondrial DNA makes up a tiny proportion of the human genome and does not tell you about traits you are likely to have, as its purpose is solely to govern the function of the cells’ energy-producing centers. However, it can still provide information regarding ancestry and is particularly useful for this purpose. As mtDNA is inherited exclusively from your mother and, like yDNA, does not undergo recombination, analysis of mtDNA allows genetic scientists to trace your maternal lineage back through potentially hundreds of generations. Both males and females can take mtDNA tests, but only to investigate the ancestry of their mother.
If you’re interested in learning more about mtDNA, take a look at reports concerning the widely publicized “3-parent baby” born in 2016, and at the concept of the “Mitochondrial Eve”.
While the primary focus of this guide is DNA testing for health purposes, many people are understandably interested in DNA tests that give insight into ancestry as well as health.
Thankfully, numerous reputable companies give you the opportunity to learn about health and ancestry. Some – like 23andMe, AncestryHealth, MyHeritage, Living DNA, TeloYears, and Vitagene – are more widely known. Others, while less advertised, can reveal more about your health. Nebula Genomics falls into this second camp.
Best for health plus ancestry testing: Nebula Genomics
Nebula Genomics sequences 100% of your genome, as opposed to the hundredths of a percentile commonly decoded by prominent companies. It isn’t alone in this; other companies like Sequencing.com offer whole-genome sequencing as well. But Nebula Genomics does it for about $100 less than Sequencing.com.
By giving you 100% of your data along with the tools to search for any gene variant that’s ever been studied and highlighted for clinical significance, you can be confident that Nebula Genomics positions you to learn the most about your health from DNA testing. For those who are interested in ancestry insights as well, the company partners with Family Tree DNA. When Nebula Genomics’ maximum accuracy and sequencing of your yDNA and mtDNA pair with Family Tree DNA’s deep experience in ancestry DNA testing and its robust database, it means you can gain deep insight into your ancestry as you learn about your health.
23andMe doesn’t offer what Nebula Genomics offers in terms of the expansive potential for health insights. It’s a lower-priced and less insightful option for genetic health testing. However, if health testing is of secondary interest to you and your primary interest is genealogical, then 23andMe could serve you better because its database is larger than Family Tree DNA’s database. So your choice hinges on whether you want DNA health reporting with a generous side of genealogy or vice versa.
Living DNA and Sequencing.com get honorable mentions here as well. For most people, 23andMe will likely be more useful for ancestry and genealogical pursuits, but both of these companies offer solid tests.
- Sequencing.com’s Ultimate DNA Test, currently priced at $69, is a great deal for health insights. This test sequences more of your genetic code and yields about 50 times more data than 23andMe or AncestryHealth. But the ancestry experience isn’t as impressive as the health reporting.
- With Living DNA, in a way, you’ll actually witness the opposite of Sequencing.com in the sense that Living DNA’s testing truly shines with ancestry, while its health offerings are less impressive. But if you know that your family tree has deep roots in Africa and/or the British Isles, and the health reporting is of lesser importance to you, then Living DNA could teach you more about your ancestry than any other test. This is where Living DNA truly shines. Learn more with our full Living DNA review.
For those of you who are interested in ancestry as well as health, here is some information about how DNA tests let you learn about ancestry as well. There are two primary goals in ancestry testing: testing for an understanding of ethnicity, and testing for genealogical purposes.
Helps answer: Who am I and where did my ancestors come from?
By analyzing your DNA and comparing it with those of various regional sample groups from around the world, DNA tests can give you broad estimates of where your ancestors likely came from. Different companies can provide different levels of location accuracy, depending on how extensive their databases are and how sophisticated their analysis is. For instance, here is a picture of my ethnicity estimates from AncestryDNA.
Ethnicity testing can provide highly accurate results on a continental level and also on certain historically smaller and more genetically isolated groups, such as Native Americans or Ashkenazi Jews. However, on a more local level the results become harder to decipher, as the free movement of people within continents has obscured differences between populations. For instance, it is easy to pinpoint a relatively small percentage of East African DNA in a European individual’s genome, but less simple to assign the majority of the DNA to a specific European country, such as France, Italy or Germany. While this ambiguity can be frustrating, location accuracy is constantly improving as more data is gathered by the service providers, and companies such as AncestryDNA now claim to be able to assign your origins to over 350 distinct regions around the world.
Helps answer: Who are my specific ancestors and living relatives?
DNA tests can help you identify relatives you never knew you had. The major testing companies have proprietary ‘relative-finding’ tools to help you. And DNA testing can help you identify recent and long-ago ancestors in your family tree. You may be surprised how far back into the past this can take you, especially if you find living relatives who are doing the same kinds of ancestry research.
There are three types of DNA test that you’ll be able to purchase from the direct-to-consumer test providers: autosomal tests, yDNA tests, and mtDNA tests. These types of test differ in how they help reveal details about ethnicity and genealogy.
Autosomal DNA tests
Anyone can take an autosomal DNA test and it’s the best place to begin ancestry testing. By far the most common type of test taken, it’s the only test necessary for satisfying most genealogy-related goals. The good news is, every provider offers autosomal testing. With some providers, like AncestryDNA, it’s the only kind offered.
Autosomal testing gives you a sweeping view of your ethnic heritage by examining the portions of your DNA that make you uniquely “you.” By comparing these genetic markers to those of various regional sample groups from around the world, DNA testing can provide you with accurate estimates of where your ancestors likely came from. You can also use autosomal testing to search for relatives on either side of your family tree, though it can’t tell you the specific branch where a match is found. Unfortunately, a process called recombination results in the random reassortment of autosomal DNA between each generation, so after a certain number of generations, the information becomes too jumbled to decode. To learn more about recombination, please visit: What is DNA recombination?
A test that examines your autosomal DNA will not tell you about your paternal or maternal haplogroups. To learn more about haplogroups, please visit: What are haplogroups?
The Y chromosome is one of two possible chromosomes (X or Y) in each person’s sex chromosome pair. Only men can take yDNA tests because only men have a Y chromosome (women have two X chromosomes); however, women can obtain the same ancestry information by asking males in their close family to take the test on their behalf – for instance, their father, brother, or paternal uncle/cousin.
One of the things that make yDNA testing powerful is that the Y chromosome does not undergo the random reassortment process called recombination that we mentioned above. This means that men inherit these portions of DNA virtually unaltered for generation after generation, and only via the male lineage, making yDNA testing perfect for exploring your paternal lineage.
mtDNA (mitochondrial DNA) makes up a very small proportion of the human genome, as its sole function is to control the energy factories of the cells (the mitochondria). Both men and women inherit mtDNA exclusively from the mother. This means that while only women will pass along their mtDNA to their children, mtDNA testing is available for men and women alike.
As with yDNA, mtDNA does not undergo recombination between generations, which means it is largely conserved and can be used for accurate tracing of your maternal lineage far back into the past.
One additional quick note: notice how we said that yDNA and mtDNA get inherited “virtually unaltered?” It’s because once in a while, a random genetic mutation will occur, which does in fact alter the inherited DNA. When a mutation gets passed down over generations and becomes prevalent to a certain degree within a population, it’s called a Single Nucleotide Polymorphism (SNP). In DNA testing, SNPs provide very important clues about your ancestral origins. For more on that, visit: What is an SNP?
Common areas of difference among test providers
Type of DNA test offered
DNA test providers vary in what types of tests they offer to you. Some offer only autosomal testing, while others offer all three types but may bundle them, making the price a bit higher. Even among the companies that provide all three types of tests, offerings vary based on how extensively the tests study your yDNA or mtDNA.
Actually, both the size and the composition of a testing company’s database are important. Generally, larger size means more accurate geographical information from ethnicity testing and that you have higher chances of being connected with living relatives. The composition of a database can also have big implications for the accuracy and detail of the ethnicity and geographic testing. A database with many samples from all over the world will be able to match your DNA to a wide range of regions, while a database with very little data from West African regions, for instance, will likely miss West African DNA in your genome. Companies vary widely in database size and composition, though they typically reveal very little or nothing about the latter for proprietary reasons. It is sometimes possible to view a list of regions covered by ethnicity testing on a company’s website, but for the purposes of comparing and choosing between the major companies, it’s generally best to focus on size.
One of the benefits of choosing a major DNA test provider is that they’ve taken the time to create user-friendly interfaces and tools to help you make the most of your test results. Major DNA testing companies offer tools to help you find living relatives, get a clear picture of your ethnic background, explore the geographic migrations of your ancestors, and, in the famous case of AncestryDNA, tie your DNA test results into the pursuit of mapping your family tree.
Some companies allow you to export your DNA data or import data from other companies. Exporting and importing data can be useful for taking advantage of another company’s database or community; you can increase your chances of finding living relatives and learning about your ancestral origins because your cousins might have chosen company A rather than your choice of company B. Additionally, many people upload their data to third-party databases like GEDmatch. Third-party databases are inexpensive and growing in popularity, but they don’t accept data from every provider; so, so if you intend to upload your results to another database it is wise to check compatibility when making your selection.
It’s probably not surprising that questions and confusion are common when studying DNA test results. Even so, people are often surprised by how much they can benefit from having a robust genealogical community connected to their DNA testing experience; it can make a big difference to what you can learn from your results, and it may determine whether your single-test experience blossoms into a deeper interest in genealogy. It’s one thing to learn about your ancestors’ migration patterns and your paternal haplogroup, but it’s another thing to have a community of more experienced and knowledgeable genealogy enthusiasts to help guide you toward a deeper and richer understanding of what it all means.
Cost varies by provider, and often different prices are available from the same provider based on a multitude of factors like the type of test offered and the extensiveness of the testing. There are also related post-testing costs that can add up in certain cases if you want to use some of the features and tools that help make the most of your results. Testing can be close to $50 or close to $500, all depending on your goals.
Historically, direct-to-consumer DNA testing was unsatisfying for those of us with non-European heritage; people who hoped to explore African, Native American, Jewish or East Asian ancestry really had a difficult time. And if you were adopted, you faced steep challenges as well. Thankfully, as the largest databases have grown more diverse thanks to a growing number of consumers, the test results have become much more useful for adoptees and people with non-European heritage. Even so, your mileage will vary from company to company, depending largely on their database, community, and the types of tests they offer.