GATA4 and Abnormal cardiac septum morphology: GATA4 mutations have been associated with numerous cardiac defects, including atrial septal defect, ventricular septal defect, atrioventricular septal defect, tetralogy of Fallot, persistent truncus arteriosus, patent ductus arteriosus, partial anomalous pulmonary venous return, as well as pulmonic stenosis in the setting of atrial septal defect.