During a survey of a selected group of residents of an institution for the mentally retarded, four previously undescribed syndromes were found. They were characterized as follows: cerebral maldevelopment, dwarfism and cataracts (autosomal recessive inheritance); cerebral maldevelopment, dwarfism and facial osteoproliferation (autosomal recessive inheritance); cerebral maldevelopment and colobomata (autosomal recessive inheritance); and cerebral maldevelopment and acrocephaly (X-linked recessive inheritance).