The proliferation of genetic testing in the 21st Century is possible thanks to breakthrough discoveries and an overwhelming interest in ancestry, supported by Ancestry.com and 23andMe. But the success of these companies has highlighted another use for personalized genetic testing: improving healthcare.
New understandings of the way an individual’s genetic makeup affects their health and the development of therapies to target specific genes are transforming the medical field. Genetics, which has come a long way since scientists determined the double-helix nature of DNA in the 1950s, can now lead to better outcomes for patients and healthcare providers alike.
Genetic tests help doctors customize care plans, catch diseases in their earliest stages, and avoid prescribing ineffective medications. By reducing trial-and-error methods, genetic testing can also save millions of dollars.
What is Genetic Testing?
A small vial of blood or saliva can reveal important insights about a person’s history and well-being. Lab tests on DNA samples may trace an inherited genetic condition to its source, indicate the presence of cancerous cells, or help diagnose a previously undetected ailment.
Genetic testing can be an umbrella term, with single-gene testing, panel testing, and large-scale genomic testing all serving different purposes. Single-gene testing, for instance, is most often used to verify the existence of a specific mutation that runs in a patient’s family.
On the other hand, the Human Genome Project mapped DNA from thousands of participants, allowing researchers to study broad population trends. In recent years, prenatal genetic tests have identified potential birth defects early in pregnancy, giving parents time to prepare and consider their options. In the same vein, professionals called genetic counselors assist people considering a test for reasons related to family-planning or personal health.
Benefits of Genetic Testing
A patient’s genetic profile can inform the course their treatment takes, because doctors can compare one person’s information to others to determine which medical interventions are best suited to help that individual recover from an illness. A genetic profile can be a crucial part of precision medicine — a multidisciplinary approach that uses individual differences in people’s genes, environments, and lifestyles to create a custom healthcare plan.
Another benefit of genetic testing is its ability to locate mutated genes before they severely impact a person’s life. This can translate to introducing preventative screenings and medicine earlier than usual. When rare diseases are identified in young children, there’s a chance that gene therapies can reverse the effects of serious symptoms. In 2017, the FDA approved one such gene therapy to treat heritable retinal dystrophy, a condition which can cause blindness and is linked to mutations of the RPE65 gene.
Beyond the immediate health improvements of genetic testing, the practice reduces reliance on trial-and-error treatments and lowers medical costs. Pharmacogenetic testing, specifically, allows medical professionals to predict a patient’s ability to metabolize certain drugs. Doctors can thus surmise which medications might adversely affect a patient and steer clear of them.
Previously, patients could be required to try a medication, report its negative side effects, and then be given another to try. Used primarily for adults, pharmacogenetic testing is a non-invasive method that may also offer children relief from chronic pain related to various illnesses. As far as costs go, pharmacogenetics could reduce the more than $500 billion spent yearly on non-optimized medication therapies.
Every area of medicine is constantly evolving, and genetics are no exception. There are valid concerns about the rise of genetic testing in patient care, and experts are working to demystify the process and rectify issues.
A frequent concern among patients is how insurance companies might use the data gleaned from DNA. If a genetic test indicates someone is living with a mutation related to a serious condition, will their rates go up?
Fortunately, no. The Genetic Information Nondiscrimination Act (GINA) of 2008 prohibits such reactions. The act prevents the misuse of genetic information in health insurance and employment decisions. GINA has removed barriers to using genetics for the public’s benefit.
Other opposition is based on the idea that individual genetic tests, which can produce false positives, will cause undue worry for patients. In January 2022, The New York Times published a story about pregnant people who were told their children showed signs of rare disorders. But the prenatal blood tests were wrong 85 percent of the time. The article points to a wider problem: Silicon Valley medical companies racing to impress consumers tend to put profit ahead of health outcomes. Combatting this means investing in tests that undergo rigorous review before hitting the market.
Geneticist Tshaka Cunningham is working to eliminate another limitation. Right now, more than 90 percent of genetic data is derived from participants of European descent. This means people of color are severely underrepresented in the very data used to determine their care. The disparity is the result of racial bias in healthcare research, as well as distrust of the medical field among Black and Latino Americans, which stems from instances of medical racism such as the Tuskegee study or the case of Henrietta Lacks. Cunningham works with the Faith Based Genetic Research Institute to demonstrate the value of genetic research and regain the trust of communities of color.
The Future of Genetic Testing in Medicine
From specialized cancer therapies to prescription painkillers, genetic testing is likely to shape the medical field for decades to come, decreasing the rate of misdiagnoses and non-optimized treatments. Access to such information can also reduce the stress on people who know certain conditions run in their family, as well as those who are uncertain about their ancestry.
The market for direct-to-consumer genetic test kits is projected to reach $1.9 billion by 2026, fueled in part by a greater cultural focus on health and wellness. Already, Medicaid, Medicare, and private insurance companies are willing to cover the costs associated with tests recommended by doctors.
As more organizations embrace genome-based medicine, knowing how to discuss its benefits and answer questions will be a great tool for all medical professionals.
Joel Landau, is founder and chairman of The Allure Group, a network of six New York City-based nursing homes.