NOTCH signalling promoted NCCs proliferation, and its inhibition resulted in decreased proliferation of NCCs.34 Moreover, Varadkar et al demonstrated that NOTCH2 was essential to the proliferation of cardiac neural crest‐derived smooth muscle cells for proper formation of the heart outflow tract.35 Ward et al reported that 76% of the chick embryos with ablated SHF at HH14 exhibited cardiac defects including pulmonary atresia and OA, while the embryos ablated at HH18 maintained normal outflow alignment. Here, NOTCH2 is linked to Pulmonary artery atresia.