Criticism about Home Genetic Testing

As much as direct-to-customer home DNA kits have been sparking interest across the globe, there has been rising criticism about them. The criticism is normally not geared at one individual company (while 23andMe are taking most the heat being the biggest and running into trouble with the FDA in the past) but rather about the concept of offering DNA kits to people and supply information which is either not accurate enough or cannot be used clinically. Everyone loved 23andMe and other home genetic test kits as long as they focused on novelty; when marketing started focusing on personal DNA kits as a diagnostic tool, that’s when all hell broke loose.

Critical articles about home genetic testing

Below you can find the most prominent articles relating to genetic home tests.

23andMe Is Terrifying, but Not for the Reasons the FDA Thinks

Scientific American starts off by describing early 23andMe’s services that focused on novelty facts that anyone can check about himself, like whether you have a Neanderthal blood in you. Then they proceed to the new 23andMe that markets itself as a useful diagnostic tool without the FDA’s permission to do so. They describe the rocky relations between 23andMe and the FDA that led to this.

Then the article shifts its focus to a completely different, but related, topic – data. Genetic home test companies have the genetic data of participants stored, and in theory, they could be reselling this information to commercial parties like insurance companies. 23andMe try to position themselves as the genetic Google, and Google, although using the catchphrase “don’t be evil” have been notorious about using the data they have gathered over the years for monetization purposes.  Although 23andMe’s T&C stipulate that the personal information stores will never be sold or shared with a third party, the other claims you have to take these guarantees with a grain of salt.


What I learned from home DNA testing

Barbara Ellen from The Guardian discusses her personal experience with DNA testing. She starts off by using the quick and cheap Thriva kit and then moving on to 23andMe. She reports the Thriva did not give her any significant results – in fact all the information and “health advice” she has received was quite generic. With 23andMe the results were quite more detailed but included a dreadful warning relating to late-onset Alzheimer’s.

The author is very critical of the supposed health benefits these companies are advertising, when in reality – they provide little information and even if they do discover something significant in one’s genetics, it is very likely to be untreatable (and has limited accuracy).


What I actually learned about my family after trying 5 DNA ancestry tests, a respectable magazine, lays out the personal experience of its writer  Tina Hesman Saey in finding clues about its family’s history through home genetic testing with 5 different companies. The companies that were used for that are Living DNA, Family Tree DNA, 23andMe and AncestryDNA.

Reportedly, results have all arrived within several weeks, but there was a great deal of variation in terms of user experience and the actual results that were yielded.

National Geographic Geno 2.0 has yielded some results relating to the deep past of the author, claiming there is a family ties with several famous figures which is hard to prove or disprove, but provided no useful results in regards to the past 500 of the family. No relatives were matches in the database.

Living DNA was very specific in regards to the author’s British roots, showing supposedly the region in which her ancestors came from. No relatives were discovered.

23andMe did a good job giving a detailed ancestry report, although the author doubts the accuracy of results, some of them did make a lot of sense to her. She also mentioned how well these results were explained – linking between physical traits to specific genes. No relatives were found and it was difficult to delve further into the family tree, though.

AncestryDNA combines a traditional genealogical records with DNA making it the most apt to create family trees, but the furthest in family it could reach was based on the inputs the writer has inserted into the software.

Overall, she says, the last 2 DNA home kits she used were fun to use and helped her develop the hobby of genealogy research, but nothing is quite “there”.


DNA testing can bring families together, but gives mixed answers on ethnicity

Tina Hesman Saey from Science News also wrote about the accuracy of ethnicity results through DNA kits. She mentions a case in which someone discovered a family through these tests he did not know of, while mentioning her experience with several of the big DNA kit providers shown a very large range of predictions. One company estimated she is 25% and another said the number is 77% making it is difficult to rely on such tests.


Say Goodbye to Privacy... Genetic Databases Allow Most to be Identified

Though many direct-to-consumer genetic testing companies claim to keep your genetic data private, several major studies have shown otherwise. A recent article in Time cites several studies showing how an individual could be identified using only a minute amount of their DNA and information from publicly available genetic databases.

While you may be concerned about your genetic privacy, not everyone is. Many people upload their raw genetic data received through at-home genetics tests to third party companies. These companies are then free to share the data where and how they please. This means that even if you are incredibly careful with your genetic data, a crazy distant cousin could easily spoil your plans. Even if you never use the service yourself, you could be identified simply based on your relationship to people who have.

This technology has already been used to identify serial killers. While you are probably not planning any serious crimes, your genetic privacy should still be concerning. Life insurance and disability insurance companies could potentially find and identify you based on your genetics. This could lead to higher premiums and more costly coverage for those with certain genes.


Read more: Is your privacy safe when doing a home genetic test?

At Home Genetic Testing an Unfortunate Development

James Evans, professor of genetics and medicine at the University of North Carolina, Chapel Hill, argues that at home genetics tests are an “unfortunate development that will likely cause considerable mischief.” In this NPR article, Evans points out the fact that interpreting the results of genetics tests is a tricky business, even for a geneticist.

Other scientists, such as President of the American College of Medical Genetics and Genomics, Dr. Louanne Hudgins, argue that direct-to-consumer genetic home tests are largely unnecessary in most cases. The article even points out that for a number of genes that indicate an increased disease risk, many people still get the disease without the gene. This happens simply because a gene is rare. Not having the gene still gives you the same chances as the general population for contracting the associated disease.

While genetic testing in general may be a future boon to society, many geneticists, doctors, and scientists are skeptical. The companies who market these products generally tend to overplay the significance of their results, either good or bad. This tends to make healthy people make less healthy decisions, like avoiding regular checkups. This also tends to make at-risk individuals overly concerned, when diet and exercise should be sufficient to lower their risk.


False Reassurance in Genetic Cancer Testing

A recently published article in the Journal of the American Medical Association (JAMA) claim that while genetic testing has a potential to help identify carriers of genes which cause cancer, a large majority of women do not carry the gene but still have a significant potential to get cancer. In other words, the environment your body is in is much more important than the genes you have.

The authors of this open letter claim that there are several reasons direct-to-consumer tests are misleading. First, they are usually not accompanied by sound advice from a doctor or geneticist. This can lead to misleading results. Second, they produce a fair amount of false-positive results, which a full-scale clinical genomic evaluation would identify. Lastly, they increase sales through fear-based marketing techniques. This leads to an increase in at-home genetics tests, but not necessarily sound cancer-prevention techniques.

In all, the major concern expressed is that genetics are too complex for the average person to understand. Even though the FDA just approved one company’s product for breast-cancer related genes, these tests are far from the whole picture. Breast cancer, like many other cancers, has a variety of causes and genetic risk is only a small component. Direct-to-consumer genetic testing often overplays this role, and causes unnecessary worry and wasted resources.

Source:  Gill, J., Obley, A. J., & Prasad, V. (2018). Direct-to-Consumer Genetic Testing: The Implications of  the US FDA’s First Marketing Authorization for BRCA Mutation Testing. JAMA, 319(23), 2377.

Alarmingly High False Positive Rate in Direct-to-Consumer Genetic Tests

A recently published article in Genetics in Medicine, the authors found that up to 40% of the time direct-to-consumer genetic tests were producing false positives. This means that almost half of the time, the results of a person’s genetics test will show that they have a gene which they actually do not carry.

The complexity of the human genome is partly to blame. Scientists have used various methods of finding and identifying genes within the genome. However, not all of these methods are 100% accurate. Specifically, as the article points out, most direct-to-consumer genetic testing companies analyze the DNA looking for single-nucleotide polymorphisms (SNPs). These tiny mutations in DNA are sometimes related to the presence of a gene, but not always. Using more advanced and rigorous techniques, these false positives could be ruled out.

But most genetic testing companies don’t seem to have time for that. A clinical genetic analysis ordered by your doctor is expensive, but thorough and analyzed by several professionals. Direct-to-consumer tests are profitable only by having high-turnover ratio and quick processing time. While this capability will likely improve in the future, it currently is a source of misunderstanding and confusion in the medical community.

Source: Tandy-Connor, S., Guiltinan, J., Krempely, K., LaDuca, H., Reineke, P., Gutierrez, S., … Tippin Davis, B. (2018). False-positive results released by direct-to-consumer genetic tests  highlight the importance of clinical confirmation testing for appropriate patient care. GENETICS in MEDICINE.

Is criticism about home DNA test just?

It’s hard to address this question because anyone who uses a home DNA kit is bound to experience something completely different. If the company that you used provides inaccurate information, or doesn’t provide you with enough output, you will become naturally frustrated about the time and money wasting involved. If your results are good and serve your purpose whether it is health or genealogy related, you are bound to be satisfied. These are all standalone cases that don’t show much one way or another, in our opinion.

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