This is part of a blog series from genetic counselors at the Basser Center. This was written by Jessica M. Long, MS, LCGC.
This past holiday season, a number of shoppers took advantage of discounts on at-home DNA testing kits; notably, 23andMe’s DNA kit was one of the top items sold in the US during Amazon’s Cyber Monday sale. Direct-to-consumer (DTC) genetic testing (also known as consumer-initiated genetic testing) has become an increasingly popular avenue to genetic evaluation. While the goal of expanding access to genetics services is a noble one and at-home testing may offer some benefits, including convenience and affordable pricing, it is vital that consumers make informed decisions, particularly when seeking a cancer risk assessment.
Increased access to genetic information
The uptick in use of DTC genetic testing highlights the increased recognition and interest in the role genetic information plays in overall health. There has been a shift among the public and medical professionals to better understand health risks (prior to development of disease), in order to maximize the opportunities for proactive health behaviors, risk-reduction, and early detection. The increased availability of genetic testing (including DTC options) has made genetic information more accessible, more familiar to patients, and thus more likely to be factored into healthcare decisions.
Affordable pricing (…but is it less expensive?)
Affordable pricing has spurred some individuals to add a DTC genetic test to their online shopping cart or sign-up for an employee wellness initiative. Increasingly, however, genetic testing ordered through your health provider’s office could actually cost less out-of-pocket, depending on insurance-specific co-pays and deductibles. Certain clinical genetic testing laboratories now offer ‘Known Mutation in the Family’ testing programs, providing free genetic testing to relatives within 60 or 90 days of the first positive test result in the family. For people with high deductible insurance plans or who lack insurance coverage, several clinical laboratories also offer patient self-pay rates of ~$250, similar to the prices offered by DTC genetic test companies.
In some circumstances, genetic testing of an elderly relative may help determine lineage (from which side of the family a known gene mutation was inherited), but may not directly influence that relative’s healthcare if other, more pressing health concerns take precedence. For this scenario, the convenience of hereditary cancer genetic testing in the home may be a priority, while also benefitting the family overall in terms of helping identify which relatives are at-risk.
When contemplating DTC genetic testing, it is important to understand not only which conditions will be evaluated, but also how thorough the evaluation will be. The question to ask is whether this is the most appropriate test to accurately assess your personal or family history of cancer. If you are unsure, it may be worthwhile to seek out the guidance of a genetic counselor prior to pursuing the test.
For example, the 23andMe Genetic Health Risk report includes information about the BRCA1 and BRCA2 genes. A gene has thousands of “letters” that make up its genetic code, and thus harmful genetic variants (called mutations) can occur in many different locations within each gene. The 23andMe BRCA1/BRCA2 (Selected Variants) test currently detects only three specific BRCA mutations most commonly observed among individuals who are Eastern European (Ashkenazi) Jewish. This test is inadequate for families who are not Ashkenazi Jewish, who harbor different BRCA gene mutations or mutations in other genes, or those with an unexplained family history of cancer.
Even for those who are Ashkenazi Jewish and receive a BRCA-positive result from 23andMe, the American College of Obstetrics and Gynecologists, the FDA, and 23andMe itself all recommend confirmatory clinical testing, prior to use in medical decision-making (not unlike the need to repeat an at-home pregnancy test at an initial prenatal visit). As another aspect to consider, while a patient may seek BRCA genetic testing for a known mutation on one side of the family, an experienced genetic counselor will also assess cancer history on the opposite side of the family; this allows determination of whether additional genetic testing or risk-reducing measures may be needed. On occasion, more than one hereditary condition may be present in the same family.
Familial cancer risk & false reassurance
Some DTC genetics tests report on minor genetic variations (called single nucleotide polymorphisms, or SNPs) that have a subtle influence on the overall chance of developing a disease. Other hereditary cancer tests, such as ones offered by Color Genomics or Invitae, evaluate entire genes for harmful mutations that can significantly increase cancer risk. Importantly, though, there are many families in which cancer risk is not explained by currently available testing, perhaps due to genes not yet discovered and/or shared environmental and lifestyle risk factors. In these circumstances, a negative (“normal”) genetic test could lead to false reassurance about a person’s risk for cancer.
A routine part of cancer risk assessment by a genetics specialist includes a thorough three-generation family history evaluation, including the use of risk estimation models to evaluate a person’s chance of developing cancer. For example, a woman with multi-generational, early-onset breast cancer in her family may still qualify for enhanced breast cancer screening, even though she and/or her relatives have had negative genetic testing.
One option provided by certain DTC genetic test companies includes the release of “raw data,” detailed genetic information that can be provided to the consumer, who in turn may use a third-party database like Promethease (which in turn uses SNPedia, a wiki-based bioinformatics web site) to learn more about the identified genetic variants. The challenge here, simply put, is that this information can be wrong; one study reported that 40% of genetic variants identified by consumers using their DTC raw data were incorrect (false positives). I personally have counseled at least two patients who uploaded their DTC raw data and determined they had a BRCA gene mutation; after repeating their BRCA genetic testing in a clinical laboratory, they were reassured to learn that the variant in question was either not present in their DNA at all or that the genetic variation was actually benign (harmless). Understandably, this had been a stressful experience for these individuals, who perhaps did not anticipate the twisting path their DTC journey would take.
A number of employee wellness plans and ancestry services have begun to offer DTC genetic testing as a chance to pursue health risk information with a goal of enabling proactive healthcare decisions. At times, I have worked with individuals who have undergone DTC genetic testing with the expectation that results would be unrevealing, given the absence of cancer in the family, but were surprised to learn of a positive result. Unanticipated positive results can be particularly distressing, especially when the associated medical recommendations can be life-altering. While one may ultimately appreciate the opportunity to reduce their risk of cancer or undergo enhanced cancer screenings, it can also feel like uncertain, uncharted territory when one does not have an immediate family history of cancer.
Genetic information and privacy
Privacy laws in the United States struggle to keep up with the breakneck speed of technology, including in the area of genetics. The Genetic Information Nondiscrimination Act (GINA) of 2008 is a federal law prohibiting discrimination by health insurance companies and employers based on genetic information. However, GINA does not apply to life insurance, disability insurance or long-term care insurance. Additionally, most of us routinely ignore privacy policies with a single online click, but it may be worth pausing to investigate how a for-profit company could use your personal and genomic health information, keeping in mind that privacy policies can change over time.
How to find a genetic counselor
Partnering with a genetic counselor serves to provide patients with an expert advocate to help them navigate the process of genetic testing and cancer risk assessment. A genetic counselor can also help illuminate who else in the family may be impacted by this information and offer guidance on ways to discuss this information with relatives. How to connect with a genetic counselor and what to expect from the discussion will be addressed in a follow up post coming soon.