Pros and Cons of Direct-to-Consumer DNA Testing
DNA testing is a helpful tool for identification, medical purposes, and ancestry that is almost 100% accurate.
It helps in criminal investigation to identify victims and establish suspects. It is used to test for genetic conditions or potential congenital disabilities. With recent improvements in technology, it is used to discover an individual’s ancestry.
Genetic testing, or DNA testing, as it is more commonly known, involves obtaining DNA from a cell sample to identify specific chromosomes, genes, or proteins, including mutations or faulty genes, and is available as a consumer product. The test will:
- Identify genetic lineage
- Confirm or rule out an inherited genetic condition
- Assess the risk of developing or passing on a genetic disorder
- Determine medications that may be most effective based on your genetic profile
There are several hundred genetic tests available, and the development of more is ongoing. The tests can be performed on:
- Body tissues
How At-Home DNA Testing Works
At-home DNA test kits use a saliva or cheek swab sample for testing, keeping the process simple. Using the cotton swab provided in the kit, swab the inside of your cheek or use the saliva collection tube. Seal the sample and send it back to the company for testing.
What You Can Find Out From An At-Home DNA Test?
Many things can be discovered through consumer product DNA tests.
Do you wonder who your ancestors are? Deep within every cell of your body are clues to their identity. They have survived plagues, droughts, fires, and floods. Your existence is because of them, but you have never had a chance to know them – until now.
Ancestry tests allow you to trace your family history much farther back than traditional genealogy records. Some even provide more in-depth detail about your family. The DNA test can tell you where you and your family came from. With more advanced tests, you can determine when your family arrived in certain locations.
A lineage-based approach is used by the lab for DNA testing. It analyzes the mitochondrial DNA, which passes through the maternal line, or analyzes the Y chromosomes DNA, which passes from fathers to sons.
During the testing, the DNA is analyzed, then run through a database comparing genetic markers with that from other individuals’ DNA on their file. As DNA is passed from generation to generation, slight mutations occur. These mutations eventually become the genetic markers that are traced back to people throughout history until today.
With an at-home DNA consumer product testing kit, your DNA is added to the company’s database. It is then compared to other samples from people who have submitted their DNA. You can look at your results online and see how many people have been found that are related to you and how close the relation is.
Because DNA ancestry tests can trace your DNA to find familial matches from the past, you can use the matches to trace how your family migrated over time from one location to another.
While most people are interested in their ancestry, DNA testing is used to reveal important health information. The best DNA tests enable you to learn about traits you inherited from your parents, optimize your vitamin routine, or allow you to embark on a weight loss treatment plan.
Types of Genetic Testing
Genetic tests have a wide range of applications both in medical and non-medical settings.
- Carrier testing is done prior to or during pregnancy to determine if you or your partner carry a gene that could cause a congenital disability.
- Diagnostic testing will confirm or rule out a genetic disorder.
- Newborn screening routinely screens for inheritable disorders as mandated by law.
- Pharmacogenetics testing determines whether your genetics may influence your reaction to drug therapies, such as genetic resistance to viruses such as HIV.
- Predictive diagnosis estimates your predisposition or risk of developing a genetically influenced disease later in life, such as breast cancer.
- Preimplantation testing screens embryos for abnormalities, which is part of the in vitro fertilization process.
- Prenatal diagnosis can detect abnormalities in the fetus’s genes prior to birth to identify birth defects or congenital abnormalities.
Non-medical uses for genetic testing consist of paternity testing to identify inherited patterns between individuals or forensic testing to identify individuals for legal purposes.
Accuracy of DNA Testing
On average, consumer product DNA testing results for medical conditions and paternity tests are 99.99% accurate. However, you can see conflicting results if you have multiple DNA tests completed by different companies. This is due to each DNA testing company having its own set of traits they test for.
This means that one at-home kit may tell you that you have the gene needed for blond hair, while another test may not mention that. That is because one company looked for that specifically, while the other one did not. It depends on the information in their database on similar ancestry data.
For thousands of years, people have moved around the world, mating with individuals of different descent and different DNA. This has made it increasingly difficult to determine a person’s region because their ancestors did not stay in one place. At-home DNA testing kit companies use the same kind of science to determine your origin.
Results from different companies may not be exactly the same, but they will be similar. The results will tell you what continent you came from, but not the specific country. There is a lot of interpretation involved in genetic genealogy. Scientists can use your DNA to calculate the likelihood of relations based on genetic markers, patterns, and variations. Genetic genealogy cannot prove them entirely, only suggest them.
Genetic genealogy helps people learn about their family history and where they came from. The DNA variations found in DNA testing provide clues about people’s predecessors and where they came from. People of particular backgrounds often share genetic variation patterns. Shared or similar variation patterns are present the closer two people are related.
What Else Can You Learn?
Some companies such as 23andMe provide recommendations for healthy changes for people with your genetic makeup. While healthy changes such as getting enough sleep and eating enough vegetables are good for everyone, this can reduce risks in some more than others, depending on your DNA.
Are you unable to handle drinks with a lot of caffeine, or do you think cilantro tastes like soap? These preferences can actually be linked to your genetic makeup. Your fear of heights, muscle composition, or whether or not you move around in your sleep can be guessed at by looking at your DNA profile.
Cons of an At-Home DNA Test
DNA Tests and Ethnicity
It is a common belief that ancestry DNA tests can tell your ethnicity or race.
An ancestry test will show some of it, but not all. DNA is tested through your mother’s mother and her mother. Or through the paternal line. These tests only analyze a small fraction of your DNA.
If you have DNA testing done and discover family members going back ten generations, you obtain information for one out of a thousand of your actual ancestors. Basically, it can give you a general idea, but not the entire picture of your race or ethnicity.
Another disadvantage of a consumer product at-home DNA testing service is that the test itself may not be accredited with the appropriate agencies. Medical tests have to attain laboratory accreditation through the federal program, Clinical Laboratory Improvement Amendments (CLIA). Not all companies selling at-home tests have this accreditation.
Interpretation and Counseling
When a physician administers DNA tests, they provide genetic counselors who help patients read the results. Without this help, the results could be misinterpreted.
The theft of online data is a continuing problem. The testing organizations do their best to keep DNA results private on their systems, but the hacking threat is impossible to eliminate. Consumers who take an at-home DNA test should be aware of this threat and determine what steps the company has taken to reduce the risk.
Test results are very personal. The individual’s family history could stir up unwanted drama or be upsetting. If you never knew you are at risk for a particular disease or opioid addiction, for example, the revealing of this fact could be difficult to hear. These companies do not have related counseling to help in dealing with this information.
A study showed that persons who were told they had a predisposition toward depression actually had worsening symptoms.
At-home consumer product DNA tests can vary in cost from $60 to $200. Consider your options before deciding the test you purchase is worth the investment financially.
Cannot Be Used for Medical Purposes
It is essential to understand that a DNA test administered by a physician is treated differently from a DNA test administered by an at-home consumer product test.
The results of the at-home tests have not been cleared for clinical use. You should not take action to treat any condition without first obtaining healthcare solutions from your doctor. If your test results show you may be at risk for a disease or condition, see your health care services provider.
Selecting a DNA Test
The information you wish to acquire determines which at-home consumer product DNA test you should purchase.
- Trace your ancestors throughout time
- Ethnicity and region estimates
- Identify relatives that have taken this test
- Build a family tree
- Cheek swab collection
- Results in 6-8 weeks
- Test covers 15 generations of maternal and paternal ancestry
- Connect with relatives up to 13 degrees removed
- Covers migration history
- Cheek swab collection
- Results in 6-8 weeks
- Over 100 million users with 9.6 billion historical records available
- Uncover ethnic and geographical origins of your ancestors
- Find long-lost relative
- Build a family tree
- Available in 40 languages
- Results in 3-4 weeks
There are other at-home consumer product DNA tests that can be purchased, such as 23andMe, 24 Genetics, FindMyPast, Family Tree DNA, Nebula Genomics, TeloYears, and Vitagene.
Science Behind DNA Testing
Deoxyribonucleic acid (DNA) is a self-replicating material present in all living organisms. It carries genetic data and a genetic code for everyone. It determines a person’s characteristics, such as hair color and personality. Every cell in the body has a complete set of DNA.
All DNA testing from two people will be 99.9% the same. There is only 0.1% of the DNA code sequence that is different from one person to the next.
This 0.1% is what makes people unique. The differences are called genetic markers and are part of the code forensic scientists use when testing DNA. When people are closely related, some of the genetic markers will be the same. Knowing where to look for these similarities and differences in the genetic code is the key to DNA testing.
DNA testing looks for a likeness in genetic markers between two or more samples. The samples can be taken from anywhere on the body because each cell in the body contains the same DNA. Hair, blood, skin, and other bodily fluids can be used for DNA testing. The more DNA available for testing, the easier it is to analyze genetic code and variations.
The DNA is divided at specific locations and points. These pieces are analyzed, and a DNA “fingerprint” is the result. By comparing two fingerprints from two different samples, they see if there is a match.
It is a fantastic technology that helps all people uncover secrets of their past. Knowing where we came from, possible medical implications, and how it helps law enforcement are benefits we all can appreciate.