The minor allele is predicted to bind TBX5 and AhR; the former has been linked to a number of cardiac phenotypes including Holt-Oram syndrome [27] and atrioventricular conduction [28] and the latter regulates cardiac size [29], a known risk factor for QT-prolongation and cardiac sudden death [30]. The gene discussed is AHR; the disease is Holt-Oram syndrome.