TBX5 and atrial septal defect: All 5 CHD-associated missense mutants in the T-box domain of TBX5 were identified from the ClinVar (M74V) (Landrum et al. 2014) and OMIM (Hamosh et al. 2005) databases, and most were identified in patients or family trios with HOS (I54T and R237W) (Basson et al. 1999; Yang et al. 2000), ASD (I101F), and VSD (R113K).