For a nominal fee, anyone with an internet connection can purchase a direct to consumer genetic test kit. Consumers simply provide a saliva sample or swab the inside of their cheek to obtain a DNA sample, mail the sample to the appropriate testing facility, and they’ll receive a detailed genetic analysis a few short weeks later. Genetic testing kits are immensely popular, too. Approximately 1 in 5 Americans has taken a direct to consumer genetic test, according to an October 2020 Consumer Reports study. Furthermore, in recent years companies like 23andMe and Ancestry have become household names.
These companies aim to provide a number of services, including connecting you with long-lost relatives, advising which country your ancestors came from, revealing your risk of certain diseases and illnesses and suggesting which diet is best for you. While at home genetic tests may offer valuable genealogical or medical insights, the results are relatively easy to misinterpret, so it’s important to take the results with a proverbial grain of salt. If, at any time, you are concerned for your health, please speak with a medical professional. The following are some of the key benefits for users of genetic testing kits:
Genetic Tests Can Help You Find Long-Lost Relatives
To determine if you could be related to another individual in their database, direct to consumer genetic testing companies will assess how many identical segments of DNA you have in common with other users. The more DNA segments you share with a particular user, the likelihood of being a genetic match increases.
Generally speaking, these predictions are very accurate. For example, relative matching tests score extremely high for parents, children and siblings. However, it should be noted that the further away a relative is in your family tree, the less certain results will be. 23andMe, for example, claims that their testing model will accurately detect relatives as distant as 3rd cousins with 90% accuracy.
While relative matching tests can help you find a long-lost family member, you could also learn something potentially shocking about a family member or distant relative. In a recent Consumer Report’s survey, upwards of 9% of survey respondents stated that these reports contained unsettling or unexpected information.
For example, it’s not uncommon for users to discover that someone thought to be a biological relative (like a father for example) is not genetically related. Unexpected discoveries like this are frequently reported by users of genetic tests, as few expected to learn about such a big family secret in such a manner.
Genetic Tests Can Help You Discover Where Your Ancestors Are From
Companies like Ancestry.com and 23andMe claim they can tell you where your ancestors originated, based on the results of your DNA test. Learning about and exploring one’s ancestry is frequently cited as one of the most common reason for taking a genetic test. Finding one’s relatives is a relatively simple process, which involves comparing your DNA with other people’s DNA.
However, estimating your genetic ancestry is a less exact science. The most common approach looks for variations in your genetic code that have a high statistical likelihood in people from certain regions. Based on those findings, the genetic testing company will provide you with an estimate of the % of your DNA that comes from such areas. For example, your test result might show that 60% of your DNA comes from Europe, while the other 40% comes from Asia.
For several reasons, it’s difficult to accurately determine genetic ancestry with at home genetic testing. Each company uses different sets of data, and the fewer samples a company has from a given region, the more limited it’s ability to confirm whether or not you have ancestors from that area. On the other hand, as more people complete one company’s test, the pool of genetic information should (in theory) become bigger and better. This, in turn, can cause a strange phenomenon wherein an individuals genetic ancestry test results can evolve and change over time.
Another concern is the limited amount of data possessed by these genetic testing companies. These databases often have genetic details on people whose ancestors came from a particular region, but ancestry stretches back much further than, say, a few generations. As such, it’s not always clear that the population you’re being compared to is the same one that was found in that location hundreds of years ago.
It’s also important to remember that a given gene variant may be more common among one group of people, but it can also appear in others. As such, finding a particular variation in your genetic blueprint does not definitively place you in any particular regional, ethnic, or racial group. In this sense, genetic ancestry tests are more akin to palm reading or horoscopes than pure, hard science.
Genetic Tests Can Reveal Your Risk for Illness and Diseases
Some genetic testing companies claim that their tests, leveraging research about variants associated with various conditions and illnesses, can assess whether you are more likely to develop a disease such as Breast Cancer or Parkinson’s disease
23andMe provides this service using technology for which it has received approval from the FDA, thus allowing the firm to sell the genetic test directly to you. Others use what is known as a “physician-mediated” test. With this approach, when you purchase a genetic testing kit, the company will enlist the support of a doctor. This allows the company to offer genetic testing services without FDA approval, so long as the test results are determined and analyzed by a federally certified laboratory.
Genetic Tests Can Tell You What Diet Is Best for You
A number of direct-to-consumer genetic testing companies have started to offer personalized diet recommendations based on your genetic blueprint. The prospect of incorporating genetic information into dietary advice is especially compelling, as it could allow a dietitian to better tailor advice and guidance to a specific individual depending on their unique genetic composition.
However, as with all things, more evidence is required to make such bold recommendations. Currently, the dietary advice from these direct to consumer genetic testing companies could be based on incomplete evidence and have the potential to yield misleading conclusions. Case in point: there are more than 900 genetic variants that may contribute to a person’s increased risk of obesity, yet many of these companies provide weight loss advice based on a mere handful of genetic variants.
Furthermore, a lot of the research about gene variants and their relationship to diet is observational and hasn’t been adequately reviewed and confirmed by peers in the health community. At best, these genetic tests can suggest a possible association between a variant and an outcome like weight loss, but they are unable to establish a cause-and-effect relationship.
At the end of the day, at-home genetic tests can provide you with certain insights about your history and your health, but it’s critically important to be aware of their limitations. Genetics are but one element of your overall health and well being. An individual’s environment, ability to access health care services and lifestyle choices play an equally important part.
As always, if you have questions or concerns about your health, please consult your doctor or health care practitioner.