Getting a DNA test is straightforward: you either order a kit online and mail in a sample from home, or you get tested through a doctor or clinic. The right path depends on what you want to learn. Home kits work well for ancestry and basic health traits. Medical genetic testing is better for diagnosing conditions or assessing disease risk. Legal tests, like paternity, require a supervised collection to hold up in court. Here’s how each option works.
Choose the Right Type of Test
Before ordering anything, it helps to know what kind of DNA test matches your goal. The three main categories serve very different purposes.
Ancestry and heritage tests are the most popular consumer option. These analyze hundreds of thousands of specific positions across your 22 non-sex chromosomes, which carry DNA from both parents and reflect all branches of your family tree. The results estimate your ethnic background by comparing your genetic markers to reference populations around the world. Some companies also offer Y-chromosome testing (which traces the paternal line from father to son) and mitochondrial DNA testing (which traces the maternal line). These are more specialized and mainly useful for deep genealogical research.
Health risk tests screen for genetic variants associated with conditions like certain cancers, heart disease, or carrier status for inherited disorders. Consumer versions give you a general picture, but clinical-grade tests ordered through a doctor are far more comprehensive and can guide actual medical decisions.
Paternity and relationship tests compare DNA between two or more people to confirm biological relationships. An at-home kit can satisfy personal curiosity, but it won’t be accepted in court. Legal paternity testing requires a supervised process with strict documentation.
How to Order a Home DNA Kit
Consumer DNA kits from companies like AncestryDNA and 23andMe are available on their websites and at most major retailers. You create an account, register your kit with the barcode included in the box, collect your sample, and mail it back in the prepaid packaging. The entire at-home process takes about 10 minutes, though your sample needs drying time before you seal it up.
Most kits use either a saliva tube or a cheek swab. For cheek swabs, you firmly rub the cotton tip along the inside of your cheek, gums, and lips for at least 60 seconds. You’re collecting cheek cells, not just saliva, so firm contact matters. Use at least two swabs, then let them air-dry upright for a minimum of one hour before placing them in the paper envelope provided. Never store swabs in plastic bags, which trap moisture and can degrade the DNA.
For accurate results, avoid eating, drinking, smoking, chewing gum, or brushing your teeth for at least one hour before collecting your sample. Rinse your mouth three times with warm water beforehand. Don’t use toothpaste or mouthwash. These precautions prevent contamination that could interfere with the lab’s analysis.
How to Get a Medical Genetic Test
Clinical genetic testing goes through your healthcare provider. Your doctor may refer you to a genetic counselor based on your personal or family health history. Common reasons for referral include a family history of hereditary cancers (such as breast, ovarian, or colorectal cancer), inherited conditions like sickle cell disease or Huntington’s disease, a history of multiple miscarriages, or a child born with a birth defect or developmental disability.
During a genetic counseling session, the counselor reviews your family tree, assesses your likelihood of carrying certain genetic variants, and helps you decide whether testing makes sense. If you proceed, the sample is typically collected in a clinical setting. After results come back, a follow-up session helps you interpret what the findings mean for your health, discusses treatment options if relevant, and connects you with specialists or support groups.
You can find a genetic counselor through the National Society of Genetic Counselors directory or locate a genetics clinic through the American College of Medical Genetics and Genomics directory. You don’t always need a referral; some genetic counselors accept self-referrals depending on the practice and your insurance plan.
What Legal Paternity Testing Requires
If your DNA results need to hold up in court, the key difference is chain of custody. This means the sample collection is supervised and documented so no one can question whether the sample actually belongs to you. At your appointment, you’ll need to present valid photo identification, which the collector will verify and photocopy. You’ll also have your photograph taken. These three elements (ID verification, a photocopy, and a photo) establish the chain of custody that makes results legally admissible.
You’ll sign a consent form before the sample is collected. If a minor child is being tested, their legal custodian signs on their behalf. The samples are then sealed and sent to the lab with documented handling at every step. Courts, child support agencies, and immigration offices typically require this level of documentation.
Cost and Insurance Coverage
Consumer ancestry and health kits generally range from $100 to $250, depending on the company and whether you add health screening to a basic ancestry package. Sales are frequent, especially around holidays, and can bring prices down significantly.
Clinical genetic testing costs more, sometimes considerably, but health insurance often covers it when a doctor recommends the test. Coverage policies vary between insurers, so it’s worth calling your insurance company before testing to confirm what’s included. Some people deliberately choose not to use insurance for genetic tests, paying out of pocket instead to keep results off their medical record.
How Long Results Take
Consumer ancestry kits typically return results in 6 to 12 weeks after the lab receives your sample. High demand can push turnaround times toward the longer end, especially during holiday seasons when kit sales spike. Paternity tests are faster, often returning results within a few business days to two weeks.
Clinical whole genome sequencing, which reads your entire genetic code, can take anywhere from a few weeks to several months depending on the lab’s workload. The process involves extracting DNA from your sample, purifying it, running quality checks, and then sequencing, with each stage adding time. A typical timeline is 2 to 3 weeks for DNA extraction and quality control, followed by 8 to 9 additional weeks for sequencing itself.
Understanding Your Results
Ancestry results break down your heritage into percentage estimates tied to geographic regions. These estimates compare your genetic markers to reference populations and can shift slightly as companies update their databases with more samples. They’re approximations, not precise measurements.
Health-related results from consumer kits often include risk assessments for specific conditions. Some use polygenic risk scores, which add up the effects of many small genetic variations to estimate your overall risk for a disease compared to others. Most people fall in the middle of the risk curve, indicating average risk. A smaller number land on either end, suggesting lower or higher risk. These scores tell you about relative risk (how you compare to others) but don’t predict when or whether you’ll actually develop a condition.
One important limitation: most large genetic studies have focused on people of European descent. This means risk scores may be less accurate for people of African, Asian, Indigenous, or other non-European backgrounds, because the reference data those scores rely on is less representative of those populations.
Privacy Protections and Gaps
The Genetic Information Nondiscrimination Act (GINA), passed in 2008, makes it illegal for health insurers to deny coverage, set premiums, or make enrollment decisions based on your genetic information. It also prohibits employers with 15 or more employees from using genetic data in hiring, firing, promotions, or pay decisions. Employers cannot require or request genetic testing as a condition of employment.
GINA has real gaps, though. It does not cover life insurance, long-term care insurance, or disability insurance. Companies in those industries can legally use genetic information in their underwriting decisions. The U.S. military is also exempt and can use genetic data for employment decisions.
Beyond legal protections, read the privacy policy of any testing company before you submit a sample. Pay attention to whether the company shares de-identified data with research partners, whether you can opt out of data sharing, and whether you can request your sample be destroyed after testing. Once your genetic data exists in a database, deleting it completely can be difficult. Some people choose consumer tests specifically to avoid having results tied to their medical records, while others prefer clinical testing precisely because results are protected under medical privacy laws.