When we got my son tested to see if there was a genetic cause for his hearing loss, there was an incidental finding that he had a mutation that could lead to Long QT Syndrome (an arrhythmia that can cause cardiac arrest during exercise or emotional stress).

His particular variant was marked as "unknown significance," but the doctors recommended he go on beta blockers immediately. We wanted to hold off and examine if there was actually a problem, since his EKG was perfectly normal and we had no family history of issues.

My husband and I both got tested, and it turned out I also carry the mutation. I did a stress test which turned out normal, and based on that info, the variant was reclassified to "likely benign."

It seems like there's a tendency to jump to conclusions that any variant in a gene where pathogenic mutations have been found is going to also be pathogenic, but that's just not the case. I think the more people who get this testing done, the clearer this will be. For a long time, people have only been tested if they already have symptoms, which means they will be biased to identify pathogenic mutations.