From Whole Exome Sequencing to Patient‐Specific Therapy: Another Example of How Basic Research Pays Off in Patient Care

I n the past 20 years, molecular genetics has successfullyentered the arrhythmia field.1,2 The identification of the genetic basis of many of the arrhythmia syndromes provided us the tools for better understanding of the pathophysiolog-ical basis of these syndromes,2 for presymptomatic testing (potentially also prenatally with the possibility of extrauterine fertilization and selection of embryos without the identified mutation) and for timely treatment of family members of a more clearly affected proband,3,4 for gene-specific therapy2 and, occasionally, also for new, mechanism-driven therapy.2 For example, gene-specific treatment has become very common in the long QT syndrome.2 Examples of truly new therapeutic modalities, envisioned only after unraveling the molecular genetic basis and the associated pathophysiolog-ical mechanism, however, are relatively scarce. A good example is the identification of flecainide as a highly effective