The genetic era is upon us. DNA is tested for a variety of reasons, from forensics and policing to ancestry and familial relationships. But the most promising applications may be in the medical field, where genetic screening can define our risk for a life-threatening condition.
One example of this is a mutation of the BRCA 1 and BRCA 2 genes, most commonly associated with an increased risk of breast and ovarian cancer. Actress Angelina Jolie brought the mutation to the forefront in 2013 when a mutation was found in her DNA, leading her to undergo a preventive double mastectomy.
The Hollywood star was prompted to get the screening when a survey of her risk factors and family history of cancer revealed an above-average threat.
Considering that family history and her age at the time, then 38-year-old Jolie was an ideal candidate for genetic testing and counseling.
“At the end of the day, testing depends on what the patient wants,” said Daniel P. Silver M.D., Ph.D., Director of Basic Science and Research in Medical Oncology at Jefferson University Hospital and leader of the Breast Program at the Sidney Kimmel Cancer Center. “But, anyone who is at a high risk should consider their options.”
At the moment, universal testing is not recommended due to a debate on the value of widespread testing.
Instead, factors like the patient’s age, current medical conditions and the prevalence of cancers—especially breast and ovarian cancers—in a personal or family history have been accepted as guidelines for eligibility. The majority of health insurance companies cover the cost of testing as long as the patients are within those guidelines.
The Problem with Going Wide
Some experts are calling for every woman to receive genetic screening. However, this is currently a minority view.
“There are a number of problems with testing everyone,” said Dr. Silver. While the cost of testing en masse could prove high, “catching and preventing cancer will eliminate cost of treatment and prove to be a good investment, and more importantly, unnecessary suffering may be avoided. However, many people prefer not to undergo testing for a variety of personal and societal reasons, and these wishes come first.”
There is also the issue of inconclusive or less comprehensive tests.
“It’s more than BRCA 1 and 2,” said Dr. Silver. “There is now a much larger group of genes. But we don’t know everything, so certain sequence changes can generate more questions than they answer, causing anxiety for patients.”
In the case of BRCA 1 and 2, mutation-negative results can also cause a patient to seek fewer mammograms, even though their risk isn’t eliminated. In reality, only a small percentage of breast cancer cases are caused by a genetic mutation, so regular mammograms are essential even if a woman tests negative for the mutation.
Emotional Considerations and the Importance of Counseling
Dr. Silver recommends counseling always be paired with the screening in order to make sense of what can be a complicated issue. A genetic counselor can help patients navigate issues with insurance, test logistics, and the emotional toll results may have on themselves and their family.
“Testing can create difficult situations, sometimes escalated by complicated family dynamics,” said Dr. Silver. This is why proper counseling before testing is so important to make sure an individual makes an informed decision to test or not. If a parent has the mutation, it means their children could also have it. There are obligations and responsibilities that can impact members of the family who might not be ready for the information.”
With these considerations, patients can take comfort in personalized delivery of test results. A major part of their encounter with the counselor is dedicated to establishing their preferences ahead of time, allowing as much discretion as they need.
At-Home Testing and Privacy
For these reasons, Dr. Silver advises being cautious with over-the-counter, at-home screening options.
“We should all be cautious about privacy issues,” he said. “As we move forward into this genetic era it’s important to protect patient privacy. It’s important to know exactly what is being done with DNA sequencing results, and not all at-home options make that abundantly clear.”
Plus, the lack of a counselor to analyze results and process emotional responses can impact a patient’s mental health.
“There is literature on how to handle these interactions the right way,” Dr. Silver said. “A great deal of care and thought are put into this discipline. Counselors are trained in all manners of interaction with patients and the importance of being sensitive to cultural assumptions and potential distress.”