KCNH2 and familial long QT syndrome: The now common approach of whole exome sequencing in diagnostic genetics for a multitude of diseases extends the challenge of rare variant interpretation, as current guidelines recommend the sharing of secondary findings in genes associated with conditions with a risk of significant morbidity or mortality.14 The common causative genes for LQTS (KCNQ1, KCNH2, SCN5A) are among the actionable ones for reporting secondary findings.15