SC5D and lathosterolosis: SC5D converts lathosterol into 7-dehydrocholesterol, and SC5D mutations cause lathosterolosis, which is characterized by growth and mental retardation, short limbs, polydactyly/syndactyly, and craniofacial malformations, including cleft palate, micrognathia, midfacial hypoplasia, and calvarial defects [66].