Genetic Testing Companies Are Facing a Racial Bias Problem in Disease Risk Tests
The large genetic studies underlying certain disease risk tests have primarily been done in populations of European ancestry, limiting their accuracy.
Earlier this year, California-based Ambry Genetics announced that it was discontinuing a test meant to estimate a person's risk of developing prostate or breast cancer. The test looks for variations in a person's DNA that are known to be associated with these cancers.
Known as a polygenic risk score, this type of test adds up the effects of variants in many genes — often in the dozens or hundreds — and calculates a person's risk of developing a particular health condition compared to other people. In this way, polygenic risk scores are different from traditional genetic tests that look for mutations in single genes, such as BRCA1 and BRCA2, which raise the risk of breast cancer.
Traditional genetic tests look for mutations that are relatively rare in the general population but have a large impact on a person's disease risk, like BRCA1 and BRCA2. By contrast, polygenic risk scores scan for more common genetic variants that, on their own, have a small effect on risk. Added together, however, they can raise a person's risk for developing disease.
These scores could become a part of routine healthcare in the next few years. Researchers are developing polygenic risk scores for cancer, heart, disease, diabetes and even depression. Before they can be rolled out widely, they'll have to overcome a key limitation: racial bias.
"The issue with these polygenic risk scores is that the scientific studies which they're based on have primarily been done in individuals of European ancestry," says Sara Riordan, president of the National Society of Genetics Counselors. These scores are calculated by comparing the genetic data of people with and without a particular disease. To make these scores accurate, researchers need genetic data from tens or hundreds of thousands of people.
Myriad's old test would have shown that a Black woman had twice as high of a risk for breast cancer compared to the average woman even if she was at low or average risk.
A 2018 analysis found that 78% of participants included in such large genetic studies, known as genome-wide association studies, were of European descent. That's a problem, because certain disease-associated genetic variants don't appear equally across different racial and ethnic groups. For example, a particular variant in the TTR gene, known as V1221, occurs more frequently in people of African descent. In recent years, the variant has been found in 3 to 4 percent of individuals of African ancestry in the United States. Mutations in this gene can cause protein to build up in the heart, leading to a higher risk of heart failure. A polygenic risk score for heart disease based on genetic data from mostly white people likely wouldn't give accurate risk information to African Americans.
Accuracy in genetic testing matters because such polygenic risk scores could help patients and their doctors make better decisions about their healthcare.
For instance, if a polygenic risk score determines that a woman is at higher-than-average risk of breast cancer, her doctor might recommend more frequent mammograms — X-rays that take a picture of the breast. Or, if a risk score reveals that a patient is more predisposed to heart attack, a doctor might prescribe preventive statins, a type of cholesterol-lowering drug.
"Let's be clear, these are not diagnostic tools," says Alicia Martin, a population and statistical geneticist at the Broad Institute of MIT and Harvard. "We can't use a polygenic score to say you will or will not get breast cancer or have a heart attack."
But combining a patient's polygenic risk score with other factors that affect disease risk — like age, weight, medication use or smoking status — may provide a better sense of how likely they are to develop a specific health condition than considering any one risk factor one its own. The accuracy of polygenic risk scores becomes even more important when considering that these scores may be used to guide medication prescription or help patients make decisions about preventive surgery, such as a mastectomy.
In a study published in September, researchers used results from large genetics studies of people with European ancestry and data from the UK Biobank to calculate polygenic risk scores for breast and prostate cancer for people with African, East Asian, European and South Asian ancestry. They found that they could identify individuals at higher risk of breast and prostate cancer when they scaled the risk scores within each group, but the authors say this is only a temporary solution. Recruiting more diverse participants for genetics studies will lead to better cancer detection and prevent, they conclude.
Recent efforts to do just that are expected to make these scores more accurate in the future. Until then, some genetics companies are struggling to overcome the European bias in their tests.
Acknowledging the limitations of its polygenic risk score, Ambry Genetics said in April that it would stop offering the test until it could be recalibrated. The company launched the test, known as AmbryScore, in 2018.
"After careful consideration, we have decided to discontinue AmbryScore to help reduce disparities in access to genetic testing and to stay aligned with current guidelines," the company said in an email to customers. "Due to limited data across ethnic populations, most polygenic risk scores, including AmbryScore, have not been validated for use in patients of diverse backgrounds." (The company did not make a spokesperson available for an interview for this story.)
In September 2020, the National Comprehensive Cancer Network updated its guidelines to advise against the use of polygenic risk scores in routine patient care because of "significant limitations in interpretation." The nonprofit, which represents 31 major cancer cancers across the United States, said such scores could continue to be used experimentally in clinical trials, however.
Holly Pederson, director of Medical Breast Services at the Cleveland Clinic, says the realization that polygenic risk scores may not be accurate for all races and ethnicities is relatively recent. Pederson worked with Salt Lake City-based Myriad Genetics, a leading provider of genetic tests, to improve the accuracy of its polygenic risk score for breast cancer.
The company announced in August that it had recalibrated the test, called RiskScore, for women of all ancestries. Previously, Myriad did not offer its polygenic risk score to women who self-reported any ancestry other than sole European or Ashkenazi ancestry.
"Black women, while they have a similar rate of breast cancer to white women, if not lower, had twice as high of a polygenic risk score because the development and validation of the model was done in white populations," Pederson said of the old test. In other words, Myriad's old test would have shown that a Black woman had twice as high of a risk for breast cancer compared to the average woman even if she was at low or average risk.
To develop and validate the new score, Pederson and other researchers assessed data from more than 275,000 women, including more than 31,000 African American women and nearly 50,000 women of East Asian descent. They looked at 56 different genetic variants associated with ancestry and 93 associated with breast cancer. Interestingly, they found that at least 95% of the breast cancer variants were similar amongst the different ancestries.
The company says the resulting test is now more accurate for all women across the board, but Pederson cautions that it's still slightly less accurate for Black women.
"It's not only the lack of data from Black women that leads to inaccuracies and a lack of validation in these types of risk models, it's also the pure genomic diversity of Africa," she says, noting that Africa is the most genetically diverse continent on the planet. "We just need more data, not only in American Black women but in African women to really further characterize that continent."
Martin says it's problematic that such scores are most accurate for white people because they could further exacerbate health disparities in traditionally underserved groups, such as Black Americans. "If we were to set up really representative massive genetic studies, we would do a much better job at predicting genetic risk for everybody," she says.
Earlier this year, the National Institutes of Health awarded $38 million to researchers to improve the accuracy of polygenic risk scores in diverse populations. Researchers will create new genome datasets and pool information from existing ones in an effort to diversify the data that polygenic scores rely on. They plan to make these datasets available to other scientists to use.
"By having adequate representation, we can ensure that the results of a genetic test are widely applicable," Riordan says.
The Friday Five: Artificial DNA Could Give Cancer the Hook
In this week's Friday Five, artificial DNA could give cancer the hook. Plus, research suggests that this daily practice can improve relationships, social media could be good for finding factual information, injecting a gel may speed up recovery from injuries, and a blood pressure medicine is promising for a long healthy life.
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
Listen on Apple | Listen on Spotify | Listen on Stitcher | Listen on Amazon | Listen on Google
Here are the promising studies covered in this week's Friday Five:
- Artificial DNA gives cancer the hook
- This daily practice could improve relationships
- Can social media handle the truth?
- Injecting a gel could speed up recovery
- A blood pressure medicine for a long healthy life
9 Tips for Online Mental Health Therapy
Research shows that, for most patients, online therapy offers the same benefits as in-person therapy, yet many people still resist it. A behavioral scientist explains how you can use it to improve mental health.
Telehealth offers a vast improvement in access and convenience to all sorts of medical services, and online therapy for mental health is one of the most promising case studies for telehealth. With many online therapy options available, you can choose whatever works best for you. Yet many people are hesitant about using online therapy. Even if they do give it a try, they often don’t know how to make the most effective use of this treatment modality.
Why do so many feel uncertain about online therapy? A major reason stems from its novelty. Humans are creatures of habit, prone to falling for what behavioral scientists like myself call the status quo bias, a predisposition to stick to traditional practices and behaviors. Many people reject innovative solutions even when they would be helpful. Thus, while teletherapy was available long before the pandemic, and might have fit the needs of many potential clients, relatively few took advantage of this option.
Even when we do try new methodologies, we often don’t do so effectively, because we cling to the same approaches that worked in previous situations. Scientists call this behavior functional fixedness. It’s kind of like the saying about the hammer-nail syndrome: “when you have a hammer, everything looks like a nail.”
These two mental blindspots, the status quo bias and functional fixedness, impact decision making in many areas of life. Fortunately, recent research has shown effective and pragmatic strategies to defeat these dangerous errors in judgment. The nine tips below will help you make the best decisions to get effective online therapy, based on the latest research.
Trust the science of online therapy
Extensive research shows that, for most patients, online therapy offers the same benefits as in-person therapy.
For instance, a 2014 study in the Journal of Affective Disorders reported that online treatment proved just as effective as face-to-face treatment for depression. A 2018 study, published in Journal of Psychological Disorders, found that online cognitive behavioral therapy, or CBT, was just as effective as face-to-face treatment for major depression, panic disorder, social anxiety disorder, and generalized anxiety disorder. And a 2014 study in Behaviour Research and Therapy discovered that online CBT proved effective in treating anxiety disorders, and helped lower costs of treatment.
During the forced teletherapy of COVID, therapists worried that those with serious mental health conditions would be less likely to convert to teletherapy. Yet research published in Counselling Psychology Quarterly has helped to alleviate that concern. It found that those with schizophrenia, bipolar disorder, severe depression, PTSD, and even suicidality converted to teletherapy at about the same rate as those with less severe mental health challenges.
Yet teletherapy may not be for everyone. For example, adolescents had the most varied response to teletherapy, according to a 2020 study in Family Process. Some adapted quickly and easily, while others found it awkward and anxiety-inducing. On the whole, children with trauma respond worse to online therapy, per a 2020 study in Child Abuse & Neglect. The treatment of mental health issues can sometimes require in-person interactions, such as the use of eye movement desensitization and reprocessing to treat post-traumatic stress disorder. And according to a 2020 study from the Journal of Humanistic Psychology, online therapy may not be as effective for those suffering from loneliness.
Leverage the strengths of online therapy
Online therapy is much more accessible than in-person therapy for those with a decent internet connection, webcam, mic, and digital skills. You don’t have to commute to your therapist’s office, wasting money and time. You can take much less medical leave from work, saving you money and hassle with your boss. If you live in a sparsely populated area, online therapy could allow you to access many specialized kinds of therapy that isn’t accessible locally.
Online options are much quicker compared to the long waiting lines for in-person therapy. You also have much more convenient scheduling options. And you won’t have to worry about running into someone you know in the waiting room. Online therapy is easier to conceal from others and reduces stigma. Many patients may feel more comfortable and open to sharing in the privacy and comfort of their own home.
You can use a variety of communication tools suited to your needs at any given time. Video can be used to start a relationship with a therapist and have more intense and nuanced discussions, but can be draining, especially for those with social anxiety. Voice-only may work well for less intense discussions. Email offers a useful option for long-form, well-thought-out messages. Texting is useful for quick, real-time questions, answers, and reinforcement.
Plus, online therapy is often cheaper than in-person therapy. In the midst of COVID, many insurance providers have decided to cover online therapy.
Address the weaknesses
One weakness is the requirement for appropriate technology and skills to engage in online therapy. Another is the difficulty of forming a close therapeutic relationship with your therapist. You won’t be able to communicate non-verbals as fully and the therapist will not be able to read you as well, requiring you to be more deliberate in how you express yourself.
Another important issue is that online therapy is subject to less government oversight compared to the in-person approach, which is regulated in each state, providing a baseline of quality control. As a result, you have to do more research on the providers that offer online therapy to make sure they’re reputable, use only licensed therapists, and have a clear and transparent pay structure.
Be intentional about advocating for yourself
Figure out what kind of goals you want to achieve. Consider how, within the context of your goals, you can leverage the benefits of online therapy while addressing the weaknesses. Write down and commit to achieving your goals. Remember, you need to be your own advocate, especially in the less regulated space of online therapy, so focus on being proactive in achieving your goals.
Develop your Hero’s Journey
Because online therapy can occur at various times of day through videos calls, emails and text, it might feel more open-ended and less organized, which can have advantages and disadvantages. One way you can give it more structure is to ground these interactions in the story of your self-improvement. Our minds perceive the world through narratives. Create a story of how you’ll get from where you are to where you want to go, meaning your goals.
A good template to use is the Hero’s Journey. Start the narrative with where you are, and what caused you to seek therapy. Write about the obstacles you will need to overcome, and the kind of help from a therapist that you’ll need in the process. Then, describe the final end state: how will you be better off after this journey, including what you will have learned.
Especially in online therapy, you need to be on top of things. Too many people let the therapist manage the treatment plan. As you pursue your hero’s journey, another way to organize for success is to take notes on your progress, and reevaluate how you’re doing every month with your therapist.
Identify your ideal mentor
Since it’s more difficult to be confident about the quality of service providers in an online setting, you should identify in advance the traits of your desired therapist. Every Hero’s Journey involves a mentor figure who guides the protagonist through this journey. So who’s your ideal mentor? Write out their top 10 characteristics, from most to least important.
For example, you might want someone who is:
- Empathetic
- Caring
- Good listener
- Logical
- Direct
- Questioning
- Non-judgmental
- Organized
- Curious
- Flexible
That’s my list. Depending on what challenge you’re facing and your personality and preferences, you should make your own. Then, when you are matched with a therapist, evaluate how well they fit your ideal list.
Fail fast
When you first match with a therapist, try to fail fast. That means, instead of focusing on getting treatment, focus on figuring out if the therapist is a good match based on the traits you identified above. That will enable you to move on quickly if they’re not, and it’s very much worth it to figure that out early.
Tell them your goals, your story, and your vision of your ideal mentor. Ask them whether they think they are a match, and what kind of a treatment plan they would suggest based on the information you provided. And observe them yourself in your initial interactions, focusing on whether they’re a good match. Often, you’ll find that your initial vision of your ideal mentor is incomplete, and you’ll learn through doing therapy what kind of a therapist is the best fit for you.
Choose a small but meaningful subgoal to work on first
This small subgoal should be sufficient to be meaningful and impactful for improving your mental health, but not a big stretch for you to achieve. This subgoal should be a tool for you to use to evaluate whether the therapist is indeed a good fit for you. It will also help you evaluate whether the treatment plan makes sense, or whether it needs to be revised.
Know when to wrap things up
As you approach the end of your planned work and you see you’re reaching your goals, talk to the therapist about how to wrap up rather than letting things drag on for too long. You don’t want to become dependent on therapy: it’s meant to be a temporary intervention. Some less scrupulous therapists will insist that therapy should never end and we should all stay in therapy forever, and you want to avoid falling for this line. When you reach your goals, end your therapy, unless you discover a serious new reason to continue it. Still, it may be wise to set up occasional check-ins once every three to six months to make sure you’re staying on the right track.