Chondrodysplasia with joint dislocations, GPAPP type (MIM 614078) is an autosomal recessive disorder characterized by short stature, brachydactyly, congenital joint dislocations, micrognathia, cleft palate, and facial dysmorphism. It is caused by loss-of-function mutations in the inositol monophosphatase domain-containing protein 1 (IMPAD1) gene. Catel-Manzke syndrome (MIM 302380) is a related disorder characterized by severe growth retardation with short and abnormal extremities, bilateral hyperphalangy, clinodactyly of the index finger, micrognathia with cleft palate and knee hyperlaxity. Some patients with Catel-Manzke syndrome have loss-of-function mutations in IMPAD1.