Characterized by a hidden defect in certain cardiac cells, the syndrome had several bizarre variants. One type results in cardiac arrest when patients hear sudden noises, like ringing from alarm clocks. Another caused a fatal rhythm problem when someone jumps into water. Suspecting that the Iowa victim had had that condition, Ackerman performed the world’s first “genetic autopsy,” using DNA extracted from her heart at autopsy, to show that she had long QT syndrome. He published the results in the New England Journal of Medicine and then determined that the woman’s surviving sister also had the problem, which was treatable.
View the original article here: Genetic tests could explain why some children and teens die unexpectedly – Washington Post