NKX2-5 and transposition of the great arteries: Mutations in NKX2-5 proteins result in a myriad of CHDs, which are mostly either atrio-ventricular conduction defects or septal defects such as ASD, VSD, hypoplastic left heart syndrome (HLHs), double outlet right ventricle (DORV), transposition of great arteries (TGA), interrupted aortic arch (IAA), cardiac outflow tract (OFT) defects, and coarctation of aorta (CoA).