Any tooth agenesis in which the cause of the disease is a mutation in the MSX1 gene characterized by varying severity of tooth agenesis that may be seen in combination with orofacial clefting in some individuals. The disease is MONDO_0007129 (tooth agenesis, selective, 1). Also known as: MSX1 tooth agenesis, MSX1-related tooth agenesis with or without orofacial cleft, tooth agenesis caused by mutation in MSX1, tooth agenesis, selective, 1, with or without orofacial cleft, tooth agenesis, selective, type 1.