mortality/aging
• all homozygotes die within 24 hours of birth
|
craniofacial
N |
• homozygotes do NOT exhibit a cleft face
|
• the overall length of the mutant skull is shorter relative to wild-type
|
• only a small portion of the frontal bone is present at its lateral basal level
|
• the interparietal bone is entirely absent
|
• only remnants of the supraoccipital bone are present
|
• only a small portion of the parietal bone is present at its lateral basal level
|
• only remnants of the alisphenoid bone are present
|
• the presphenoid bone at the base of the skull is absent
|
• only remnants of the squamosal bone are present
|
• homozygotes display absence of the cranial vault
|
short maxilla
(
J:33716
)
• only remnants of the palatine bone are present
|
• all homozygotes display an acrania/meroanencephaly phenotype
• mutant pups delivered by caesarean section at E18.5 are alive with exposed and degenerating brain tissue, suggesting that lack of brain tissue is due to cannibalism by the mother
• folic acid treatment suppresses the development of the acrania/meroanencephaly phenotype but does not rescue the brain defects that compromise neonatal viability
|
• the nasal cartilages are severely affected: the lamina cribrosa and turbinate cartilages are missing and the cartilaginous nasal capsule is misshapen
|
• the cartilaginous nasal capsule is misshapen
|
hearing/vestibular/ear
N |
• homozygotes display no defects in the cartilages and ossicles of the middle ear
|
skeleton
N |
• homozygotes display no obvious defects in the limbs, trunk bones or visceral organs
|
• the overall length of the mutant skull is shorter relative to wild-type
|
• only a small portion of the frontal bone is present at its lateral basal level
|
• the interparietal bone is entirely absent
|
• only remnants of the supraoccipital bone are present
|
• only a small portion of the parietal bone is present at its lateral basal level
|
• only remnants of the alisphenoid bone are present
|
• the presphenoid bone at the base of the skull is absent
|
• only remnants of the squamosal bone are present
|
• homozygotes display absence of the cranial vault
|
short maxilla
(
J:33716
)
• only remnants of the palatine bone are present
|
• all homozygotes display an acrania/meroanencephaly phenotype
• mutant pups delivered by caesarean section at E18.5 are alive with exposed and degenerating brain tissue, suggesting that lack of brain tissue is due to cannibalism by the mother
• folic acid treatment suppresses the development of the acrania/meroanencephaly phenotype but does not rescue the brain defects that compromise neonatal viability
|
• the nasal cartilages are severely affected: the lamina cribrosa and turbinate cartilages are missing and the cartilaginous nasal capsule is misshapen
|
• the cartilaginous nasal capsule is misshapen
|
nervous system
• at E9.5, the neural tube in the entire forebrain region is closed; in contrast, the neural tube in the midbrain region is wide open from the forebrain/midbrain boundary and appears everted
• from E10.5 to E15.0, the neuroepithelium in the midbrain region proliferates and the forming brain tissue remains exposed
• at later stages, the malformed brain tissues begin to degenerate leading to anencephaly
|
• at E9.0, homozygotes display loss of forebrain mesenchyme cells due to apoptosis; as a result, forebrain neural tube closure is initially blocked
• at E9.5, the forebrain becomes repopulated with mesenchymal cells; however, initiation of neural tube closure at the forebrain/midbrain boundary never occurs
|
• all homozygotes display meroanencephaly
|
respiratory system
• the nasal cartilages are severely affected: the lamina cribrosa and turbinate cartilages are missing and the cartilaginous nasal capsule is misshapen
|
• the cartilaginous nasal capsule is misshapen
|
embryo
• at E9.5, the neural tube in the entire forebrain region is closed; in contrast, the neural tube in the midbrain region is wide open from the forebrain/midbrain boundary and appears everted
• from E10.5 to E15.0, the neuroepithelium in the midbrain region proliferates and the forming brain tissue remains exposed
• at later stages, the malformed brain tissues begin to degenerate leading to anencephaly
|
growth/size/body
• the nasal cartilages are severely affected: the lamina cribrosa and turbinate cartilages are missing and the cartilaginous nasal capsule is misshapen
|
• the cartilaginous nasal capsule is misshapen
|