Using genetic counselors vs at-home tests: The future of genetic testing | Quantumrun

Using genetic counselors vs at-home tests: The future of genetic testing

Home / Super Human
By Kathleen Li
@Quantumrun
Jun 17, 2018,  12:16 PM

In 2013, Angelina Jolie introduced the public to genetic screening when she decided to have a double mastectomy. She chose to undergo surgery because she tested positive for a mutation in the BRCA gene, a gene category linked to an increased chance of cancer (Jolie). In fact, the presence of BRCA1 or BRCA2 variants increases the risk for breast cancer by age 80 from 12% to 72% and 69%, respectively (National Cancer Institute). Faced with those odds, Jolie not only went under the knife, but she also wrote an opinion editorial for the New York Times urging women to pay to screen themselves for their potential predisposition to cancer. This lead to a phenomenon known as the “Jolie Effect,” where there was an increase in the number of women who had genetic screenings for breast cancer done. 

Now, we may see another surge in genetic screenings—but this time, without the genetic counselors. As of April 2017, the FDA now allows the marketing of direct-to-consumer (DTC) tests for genetic risk of Parkinson’s, late-onset Alzheimer’s, and Celiac Disease, among others (FDA 2017). More recently, the FDA has also allowed the DNA testing company 23andMe to offer breast cancer screening by testing for the BRCA1 and BRCA2 genes (FDA 2018). This change of regulation has the potential to change how we get our genetic tests done completely. Thus, a point of contention is whether we should recommend genetic counselors for genetic tests, as opposed to the more accessible DTC model. As it currently stands, direct-to-consumer genetic tests seem to have more benefits than drawbacks.

How does DNA testing work?

The cheek swabs that genetic testing companies ask you to do scrape off small amounts of skin cells. Therefore, these companies can break down the nucleus, where DNA is stored, and replicate this DNA through a process called PCR to get several thousand copies. They don't read your entire genome—that would take too long—instead, the workers at DTC testing companies look for patterns at specific locations of your DNA. That pattern would indicate what variation of a gene you have.

DTC tests are less financially and socially intimidating

One of the main advantages of DTC testing is that it alleviates the financial burden previously associated with genetic testing. In the Johns Hopkins Medical Center, for example, a general genetic test costs $3,400, and testing for a specific mutation like BRCA variants costs about $500 (Brown). In comparison, the "Genetic Health Risks" test package from 23andMe costs $199 (23andMe). The power of direct genetic access is that consumers pay less.

The financial and practical issues of requiring medical professionals for genetic testing deter the majority of people from doing these screenings. Genetic counselors often have a backlog of clients, especially since the demand for genetic testing is growing faster than the pool of experts. In fact, studies found that requiring a genetic counselor deters patients from getting a genetic test in the case of breast cancer—test cancellations rates rose from 13.3% to 42.1% when counselors were required for a screening for BRCA1/2 (Whitworth et al). Groups belonging to African or Latin American descent had even higher cancellations rates of 49%. Therefore, the requirement of using genetic counselors for genetic counseling not only discourages lower-income families, but also may discourage minorities, leading to those groups being more unaware of their genetic risk of diseases.

Possible drawbacks

Critics of DTC genetic testing argue that the expertise of genetic counselors is required for the patient to better understand their risk and take the appropriate steps to minimize it. Erica Ramos, the president of the National Society of Genetic Counselors, claims these costly consultations are necessary because most people will not understand the results properly: "Genetic counselors can help [people] be prepared for what the results may tell them, identify other clinical tests that may be needed based on their history and understand how those results could affect them and their relatives” (NSGC).

Current research is contradictory on whether genetic counseling actually has any benefit. On one hand, an analysis by Amanda Singleton found that customers who purchase DTC tests may misinterpret results to either gain a false sense of security or develop unjustified amounts of anxiety (Singleton et al). A percent risk of a disease is not a guarantee that one will develop that disease later, since genetic diseases are also influenced by environmental factors, like carcinogens, for example. It is the role of genetic counselors to interpret family history and other aspects of the patient's life to determine their actual risk.

On the other hand, a review of multiple studies found that genetic counseling on familial cancer had no significant effect on risk perception, general anxiety, general distress, or depression (Braithwaite et. al). Although there was an increase in knowledge about the respective diseases, the patients weren't emotionally affected and didn't change their behaviors in response to this new knowledge. According to this study, the presence of a genetic counselor wouldn't have any lasting positive effect.

How to proceed

Nevertheless, DTC genetic testing companies should take care not to word their results in a vague or misleading manner. Studies from the Government Accountability Office and the Evaluation of Genomic Applications in Practice and Prevention working group have found that several companies used vague wording that could potentially cause confusion (Singleton et al.). Similarly, the new the 23andme BRCA variant screening service only identifies three variants of that gene out of over a thousand possible mutations and doesn’t screen for other genes also linked to breast cancer (FDA 2018). Therefore, if a customer tests negative for those three variants, they may still be at risk for cancer.

Impact (ONLY use the 'Paste From Word' button to safely copy and paste text from a Word doc) 

Overall, genetic counseling has become impractical to meet the large demand for genetic tests because of its current prohibitive cost, relative unavailability, and ultimately, because of how it disproportionately discourages minorities and low-income groups from undergoing testing. DTC genetic testing companies may provide an opportunity for more screenings than genetic counselors, but they must be careful in how they inform consumers of their respective risks. These at-home services should have more restrictions and guidelines on how they report personal results, especially since this system has a large potential for causing psychological distress or failing to diagnose or warn individuals properly. Should DTC genetic testing continue to develop responsibly, it has the potential to increase awareness of genetic risk among a broader range of the public.

Forecasted start year: 
2018 to 2020

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