GATA4 and Abnormal cardiac septum morphology: Since then, additional human genetic studies, by us and others, have demonstrated that mutations in GATA4 are associated with pulmonic valve stenosis that occurs in conjunction with atrial septal defects, or as part of tetralogy of Fallot, supporting a potential role for this transcription factor in semilunar valve disease (Okubo et al., 2004; Sarkozy et al., 2005; Nemer et al., 2006; Tomita-Mitchell et al., 2007).