ROCHESTER, Minn. – The story of a family who turned to Mayo Clinic for a second opinion after more than 20 of them were diagnosed with a possibly life-threatening heart condition is highlighting the potential dangers of genetic testing when it’s used incorrectly.
After the tragic death of a 13-year old boy, his family was told that long QT syndrome was not only the cause of his death, but that genetic testing found that many of the family members also had long QT syndrome. One of the boy’s siblings even received an implanted defibrillator because of the supposed diagnosis.
The family turned to Mayo Clinic experts for a second opinion. Genetic Cardiologist Michael Ackerman, M.D., Ph.D. and his team were suspicious of the diagnosis because none of the family members were showing any symptoms of long QT syndrome. Ackerman explains they had good reason to be suspicious because 30-40% of patients who come to Mayo with a diagnosis of long QT syndrome end up leaving without that diagnosis. Ackerman and his team started over and looked into the root source, the 13-year-old boy and performed a molecular autopsy.
“We started from stem to stern looking through his genetic code and comparing that to his mother and father’s,” Dr. Ackerman explains.
By doing so, they found the answer; the boy had a completely different genetic heart defect than the one that causes long QT syndrome and importantly for the family, that genetic heart defect belonged to him and him alone. Because of inappropriate use of genetic testing and incorrect interpretation of the test results, the family was misdiagnosed.
“Doing the genetic testing the right way gave this incredibly powerful thing of closure for the family,” Ackerman explains. “And clarity for the family as to what to do for the rest of the family members, which was nothing. They’re all healthy.”
He says this story is an example of the right way to do precision medicine, verses the wrong way.
“We’re in an incredible era of medicine, this genomic medicine, this precision medicine, this individualized medicine is amazing and it’s really going to transform medicine. But, we’re right now a little bit in the wild west. We have those who are wise users of the tests, and even wiser interpreters of the tests, and we have those who are not using genetic testing wisely.”
In some cases, he says the ability of physicians to interpret results of genetic sequencing has not kept pace with how rapid the technology has advanced.
“We just really need to continue the efforts of making the physician community aware of what genetic testing can and cannot deliver,” he adds.
Co-authors are: Jaeger Ackerman, Jamie Kapplinger, David Tester, all of Mayo Clinic; Daniel Bartos, Ph.D., University of Kentucky and University of California, Davis; and Brian Delisle, Ph.D., University of Kentucky.