In addition, a missing upregulation of CITED2 by MYRF in heart development might also be the cause for abnormal pulmonary venous return to the right atria, atrial septal defect (ASD) or tetralogy of Fallot (ToF), as well as a left–right patterning defect that is observed in humans with heterozygous CITED2 variants and Cited2−/− mice [31,41]. This evidence concerns the gene CITED2 and atrial septal defect.