If you were at high risk for a genetic disease, would you want to know?
If so, would you feel comfortable gleaning this information for a medical kit at your home?
This may be how more and more people will be obtaining these important diagnoses in the near future.
Genomic testing company 23andMe has received Food and Drug Administration (FDA) approval to tell customers whether they have an increased risk of developing certain conditions.
The company was initially banned in 2013 from providing this data over fears these genetic tests were being misrepresented as medical advice.
The Silicon Valley company’s risk tests are for Alpha-1 antitrypsin deficiency, celiac disease, early onset primary dystonia, Factor XI deficiency, Gaucher’s disease type 1, glucose-6-phosphate dehydrogenase deficiency, hereditary hemochromatosis, hereditary thrombophilia, late onset Alzheimer’s disease, and Parkinson’s disease.
A genetic expert says these tests can provide some interesting information, but she adds that anyone who’s truly interested in learning about genetic risk factors should visit a genetic counselor.
“There’s been a lot of articles published on this lately, but the quick summary is that previously there were companies that offered direct consumer genetic testing that reported on health conditions,” said Mary Freivogel, MS, CGC, president of the National Society of Genetic Counselors (NSGC) Board of Directors. “There were a few previously that aren’t around anymore. 23AndMe was one that a while ago did report on health risks, and the FDA cracked down on them and said, ‘You can’t do this anymore.’ So they continued to exist, but they only reported information on stuff like ancestry and wellness characteristics.”
A growing trend
23andMe may be among the most prominent companies that allow consumers to mail samples in for analysis, but they’re hardly the only player in the field.
Ancestry.com is one of companies that offer DNA testing to give consumers insights on their ancestry, while a host of other companies specialize in paternity and forensic testing.
While these tests can provide consumers with entertaining information about themselves, the possibility of this data being misinterpreted is a major concern for genetic experts.
One of the issues with direct-to-consumer genetic testing is that these tests tend to paint in broad strokes, says Freivogel.
“These tests are testing for certain genes that are associated with very specific conditions,” she said. “Just to give you an example, for Alzheimer’s, they’re testing for a gene called APOE. If you have a specific version of that gene, your risk to develop Alzheimer’s is higher. It’s not 100 percent, but it’s higher than average. However, there are other genes that are responsible for Alzheimer’s running in families as well. And there’s actually another gene that causes early onset Alzheimer’s that’s not tested for by the 23andMe test. So is the 23andMe test accurate in telling you if you have a specific version of the APOE gene? Yes. But is it accurate in telling you your risk for Alzheimer’s? Maybe, but maybe not. Because if you have a mutation in a different gene, then it’s going to completely miss that, and it’s going to give somebody false reassurance that their risk for Alzheimer’s is average when in actuality it might be very high.”
In other words, says Freivogel, genetics are far more complicated than a take-at-home test might lead one to believe. These tests detect variations in different genes that can provide insights on how genetics could influence the risk of developing a disease, rather than predicting whether or not that disease will develop.
Because of this, and also the fact that genetic factors rarely act alone, guidance from an expert is the safest course of action, says Freivogel.
“I think my major concern is that, depending on the patient’s family history, they may need additional genetic testing, and the family history is going to clue you into that,” she said. “And that’s what’s being removed with take-at-home genetic tests. There’s really no analysis of that family history. If you know their family history and can say, ‘Wow, there are three individuals in this family that had early-onset Alzheimer’s that’s linked to a different gene not included on this panel,’ we can order additional genetic testing for that gene. So that’s the piece that’s removed from this.”
Professional genetic counseling can also provide patients with guidance for news that could be unpleasant to hear.
“These tests don’t include education on what the test is going to tell you,” says Freivogel. “Are you prepared to know that you’re at increased risk for a disease that you can’t do anything about? Are you prepared to share this information with family members?”
23andMe explicitly states that their service is not a diagnostic tool, and that the recent FDA approval of their product is partially dependent on the user’s ability to comprehend the results.
“Anyone with concerns about their results, or with a family history of a condition, should consult a medical professional or genetic counselor to discuss the best next steps,” a 23andMe spokesperson told Healthline. “In working with the FDA, we conducted user comprehension testing on the key concepts of Genetic Health Risks and the possible scenarios conveyed in these types of reports. As part of the FDA review process, that testing had to meet a certain threshold for user comprehension of the key concepts presented in the reports. This was assessed by user testing across a wide range of demographic characteristics in a controlled lab-based setting.”
Take the test, but talk to an expert
There’s no doubt that direct-to-consumer genetic tests have a broad appeal. They’re easy to take, relatively inexpensive, and can provide interesting and accurate data about a person’s ancestry.
But it’s crucial for people to understand just what kind of information these tests include, as well as how to interpret the results when they get them.
“I always encourage patients to include their primary care physician in the discussion,” said Freivogel.
While FDA approval can be a tricky process, there can be little doubt that direct-to-consumer genetic testing will only expand in the years to come.
“We expect to release additional reports in the coming months,” the 23andMe spokesperson said. “We can’t speculate on specific reports or timing on when they may be available, but you can expect that we will continue to work to provide reports that are in high demand and are meaningful to existing and new customers. We are very excited about our future. With the help of our customers who consent to participate in research, we hope to develop therapeutics for serious unmet medical needs and foster a more personalized approach to medicine.”