Heterozygous mutations in transcription factor gene NKX2‐5 are connected to either isolated or combined congenital heart disease (CHD), primarily secundum atrial septal defect‐II (ASD‐II), ventricular septal defect (VSD) or tetralogy of Fallot (TOF). The gene discussed is NKX2-5; the disease is Tetralogy of Fallot.