Abstract

A brother and sister with mental retardation, malformations of the cerebellar vermis, characteristic 'metronome' eye movements, lingual hamartomas, and postaxial polydactyly are described. The clinical overlap with the OFD group of syndromes, in particular OFD III and OFD VI, and Joubert's syndrome is discussed. If OFD III syndrome is to be recognised as a distinct entity, these two cases represent the second and third cases reported.