Schuffenhauer et al, first reported the role of PAX9 in a patient presented with bilateral CLP.60A linkage analysis ofPAX9gene in two large families and four unrelated families showed that the hypodontia primarily involving molars, suggested that the mutant PAX9 protein acquires functional defects in DNA binding, as well as the loss of function of PAX9 resulting in haploinsufficiency during the morphogenesis of the dentition and the subsequent tooth agenesis.61, 62Several studies identified mutations at PAX9 may increase the risk of NS cleft lip with or without palate.63, 64, 65, 66. The gene discussed is PAX9; the disease is cleft lip.