| A rare genetic intellectual disability syndrome with characteristics of severe global developmental delay with intellectual disability, microcephaly, growth retardation, ocular defects such as congenital cataract and nevus flammeus simplex on the forehead. Cardiac, urogenital, and skeletal abnormalities, as well as seizures are present in most patients. Dysmorphic craniofacial features include sparse hair, downslanting palpebral fissures, hypertelorism, broad and overhanging nasal tip and short philtrum among others. The syndrome is caused by homozygous variants in the MED25 gene (19q13.33), coding for a component of the mediator complex. This complex is required for transcription of most RNA polymerase II-dependent genes. Transmission is autosomal recessive. |
