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Genetic Linkage

My New View of DTC Genetic Testing

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“Are you still collecting stories about DTC testing? I've got one for you!” my grad student L.W. e-mailed a few days ago. Little did I know her family's experience would change my mind about direct-to-consumer genetic testing.

L.W. had taken my online course “Genethics” in 2008 for the master’s program at the Alden March Bioethics Institute of Albany Medical College. For one assignment, students choose a DTC testing company, peruse the website, and indicate 3 tests that they would take and 3 that they wouldn't – and why.

As a class activity, L.W. didn’t really approach the testing seriously. “It's fun cocktail party info. ‘Why, yes, I'd love another mocha cappuccino at 9 pm. No problem... I'm a fast caffeine metabolizer!’”

But then a year ago, her mother was diagnosed with breast cancer, and the idea of genetic testing returned with a new sense of urgency.

L.W. knew her family came from somewhere in eastern Europe, but she'd never heard anyone talk about Jewish ancestors who might have handed down a BRCA mutation. She didn't know of any other cancer cases, but a few relatives had Parkinson’s disease. So while her mother struggled through surgery and chemo, too upset to think about genetic testing, L.W. sent her own DNA-bearing saliva sample to 23andMe.

The company sent back results on dozens of traits as well as ancestry information, including the three BRCA mutations that are more common among Ashkenazi Jews, which L.W. thought she wasn’t. But the ancestry tests said otherwise.

Months later, her mom finally had full-gene conventional testing once her insurance company agreed to cover the high price tag from Myriad Genetics, which owns the patents on the complete gene sequences. Lo and behold, L.W.’s mother had one of the Ashkenazi mutations.

“She was devastated, largely out of fear for her children, grandchildren, nieces, and nephews. Before I could even process the implication of the news for myself and my own children, I remembered the 23andMe test I’d taken for the mutations that Myriad Genetics doesn't own under its patents. I was negative!” L.W. told me. Her chance of having the mutation, given her mother’s genotype, was actually 50%, not the minuscule risk she’d expected when she sent in her spit.

But L.W.’s joy quickly faded to doubt. Were the test results “clinically actionable”? After all, the 23andMe website proclaims: THIS SERVICE IS FOR RESEARCH AND EDUCATIONAL USE ONLY; not medical diagnosis or advice.

So L.W. sought further information from 23andMe and Myriad Genetics. 23andMe never responded, perhaps lest doing so would suggest support of using their information in clinical decision-making, but a very helpful genetic counselor from Myriad Genetics did, reassuringly.

L.W.'s mother's genetic test took more than a year, given the insurance battle and having genetic counseling, but the full sequencing was necessary because she hadn’t known or acknowledged her Jewish heritage. The cheaper three-mutation test might have missed mutations. But many people in this particular family are grateful for 23andMe's solution.

“I can't tell you how relieved we all were to know that at least some of us will be spared the agonizing choices that come with BRCA mutation knowledge. I'm also incredibly grateful that there is a $99, spit-in-a-cup option available for those members of my family who are unable or unwilling to get the expensive blood test,” L.W. said. As a grad student in bioethics who has worked in the genetics field, however, she understood the complexity of genetic testing for breast cancer. But I worry about the general public.

Myriad Genetics has been in the news so often, as the case against gene patenting winds its way to the Supreme Court, that the availability of tests for the common BRCA mutations isn’t widely known. The February issue of More magazine, for example, has an article about gene patenting that talks only about the full gene sequencing, perpetuating the misinformation that the $3,300 test is the only one to detect BRCA cancers. All it takes is a look at genetests.org to find a lab offering targeted mutation tests.

L.W.’s DTC genetic testing experience, begun as a class assignment and fueled, eventually, by curiosity and medical need, had a positive outcome: she’s relieved, and the rest of her family can be tested. A bonus: L.W. and her mom joined a study on the family’s Parkinson’s gene. “We decided to be part of a natural history study of LRRK2 at the National Institutes of Health, where hopefully we can help contribute to the general scientific knowledge base,” L.W. said.

I can still recall the pandemonium of negative reactions at the 2007 American Society of Human Genetics annual meeting when the first three DTC companies announced their programs. I was among the outraged crowd. But maybe DTC genetic testing just needed time to prove its value. My student’s case is a clear win-win situation.

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