237x237px The disorder is characterised by the absence of the mandible (agnathia), with the ears fused together just below the chin (synotia). In addition to agnathia and synotia, other symptoms that may manifest in<unk>  include: * Facial/musculoskeletal * Small (microglossia) or absent (aglossia) tongue * Small (microstomia) or absent (astomia) mouth * Cyclopia with proboscis * Median cleft lip and cleft palate * Neurological * Holoprosencephaly * Agenesis of the corpus callosum * Anencephaly or other neural tube defects * Organ systems * Situs inversus (full rotation of the internal organs) * Cardiac anomalies * Ambiguous genitalia * Absence of glands Grades Sewall Wright described twelve grades of<unk>  in guinea pigs. Grades 1 to 5 were isolated agnathia with no neurological defects. Grades 6 to 9 featured severe holoprosencephaly. Grades 10 to 12 featured aprosopus (absence of the face and most of the head) with absence of the prosencephalon and mesencephalon. One human case corresponding to a high Wright grade has been reported in modern history.
Otocephaly
Möbius syndrome
Oxycephaly
Treacher Collins syndrome
Plagiocephaly
Goldenhar syndrome
Cebocephaly
Trigonocephaly