Congenital heart defects (atrial and ventricular septal defects [15,18,29], the tetralogy of Fallot [39], tricuspid valve atresia, pulmonary artery stenosis, and the transposition of the great arteries [13,25]) are described in up to 93% of patients with GATA6 syndrome [17]. Here, GATA6 is linked to ventricular septal defect 1.