A very rare syndrome with characteristics of intellectual deficit, postaxial polydactyly and epilepsy. To date, seven individuals in three families have been reported. Facial features are not characteristic except for a prominent jaw. Concordant features in all subjects are postaxial polydactyly, which in four individuals affect also the feet, and intellectual deficit, which is usually severe, with absent or indistinct speech. Seizures are common with onset in the first months of life or in early childhood. Cutaneous syndactyly, camptodactyly and clinodactyly of fingers and brachydactyly and syndactyly of the toes have been recorded.