Mandibulofacial dysostosis with microcephaly (MFDM) is a rare autosomal dominant congenital anomaly syndrome. Affected patients have been primarily described as presenting with microcephaly, midface hypoplasia, micrognathia, characteristic external ear abnormalities, and significant global developmental delay. In addition, several affected individuals have also presented with delayed brain myelination and abnormal white matter on magnetic resonance imaging (MRI), choanal and aural atresia, cleft palate, congenital heart defects, bilateral hearing loss, cryptorchidism, proximally placed thumbs, and expressive language delay. Haploinsufficiency of a spliceosomal GTPase, EFTUD2, is responsible.
