mortality/aging
• about 16.4% die shortly after birth with exencephaly
(J:13045)
• folic acid supplementation prolongs survival
(J:58433)
|
• about 24% die after implantation
|
• about 23.6% are pre-implantation lethals
(J:13045)
|
growth/size/body
• lower incisors are greatly reduced
|
• since there are no erupted lower incisors, there is continous growth and inward curving of the upper incisors; the teeth force themselves against the palate, cause ulcerations, inanition, and death
|
• crown cusp pattern of the molars is abnormal
|
• all mutants (30 of 30) show absence of at least one third molar
(J:12998)
• most mutants have no third molars at all; only 3 of 30 mutants have just one third molar missing
(J:12998)
• males are more severely affected than females
(J:12998)
• however, upper and lower jaws are almost equally affected, with no differences between right and left
(J:12998)
|
• all molars are significantly reduced in size; however, the greatest size reduction is confined to the third molars which tend to be absent
(J:12998)
• the first molars are moderately reduced while the second molars are considerably reduced in size
(J:12999)
|
• tooth germs that give rise to the third molars reach the cap stage but do not invaginate to form a bell
• regression of the third molars begins earlier and lasts longer, beginning on the 5th day instead of the 6th day in controls
|
• reduced and/or unerupted lower incisors
(J:13045)
|
• molar development is slightly delayed such that at P3, when the enamel organ has reached the bud stage in wild-type, it is still in the early bud stage in mutants; this difference persists up to P8
|
• 4 of 17 mutants have bent noses; the nasals are not aligned with the medial suture of the paired frontals
|
• small mutants have elongate and pointed heads
|
• occasionally small mutants have inclined pinnae
|
• mutants are significantly smaller at birth and remain so thereafter
|
• about 28% of mutants are 1/2 to 1/3 the size of control littermates
(J:13045)
• about 40% of the animals successfully complete neural tube closure but are runted
(J:58433)
|
• the small mutants appear growth retarded and smaller around 16-20 days of age
|
nervous system
• variable penetrance of exencephaly; mutants with exencephaly are normal sized
(J:13045)
• 20% exhibit exencephaly
(J:58433)
• the neural folds in the mesencephalon remain separated in the midline and splay over the skull base
(J:58433)
• females more than males display exencephaly
(J:58433)
• folic acid supplementation reduces the risk of exencephaly by as much as 55%; females are more responsive to the folic acid than males
(J:58433)
• mice display cranial but not spinal neural tube defects
(J:101423)
|
skeleton
small cranium
(
J:13045
)
• mutants exhibit an inter-orbital pinched appearance of the frontals
|
• cranial bones are thinner
|
• lower incisors are greatly reduced
|
• since there are no erupted lower incisors, there is continous growth and inward curving of the upper incisors; the teeth force themselves against the palate, cause ulcerations, inanition, and death
|
• crown cusp pattern of the molars is abnormal
|
• all mutants (30 of 30) show absence of at least one third molar
(J:12998)
• most mutants have no third molars at all; only 3 of 30 mutants have just one third molar missing
(J:12998)
• males are more severely affected than females
(J:12998)
• however, upper and lower jaws are almost equally affected, with no differences between right and left
(J:12998)
|
• all molars are significantly reduced in size; however, the greatest size reduction is confined to the third molars which tend to be absent
(J:12998)
• the first molars are moderately reduced while the second molars are considerably reduced in size
(J:12999)
|
• tooth germs that give rise to the third molars reach the cap stage but do not invaginate to form a bell
• regression of the third molars begins earlier and lasts longer, beginning on the 5th day instead of the 6th day in controls
|
• reduced and/or unerupted lower incisors
(J:13045)
|
• molar development is slightly delayed such that at P3, when the enamel organ has reached the bud stage in wild-type, it is still in the early bud stage in mutants; this difference persists up to P8
|
• 95% have abnormal caudal vertebrae
(J:13045)
|
• seen on a rare occasion
(J:13045)
• misshapen or fused vertebrae
(J:101423)
|
• many caudal vertebrae are shortened, some so much that they appear as bone fragments
|
• 68.75% have lumbar abnormalities
(J:13045)
|
• 26.5% have sacral abnormalities
|
hemivertebra
(
J:101423
)
• delayed skull ossification
|
• slower closure of sutures
|
craniofacial
small cranium
(
J:13045
)
• mutants exhibit an inter-orbital pinched appearance of the frontals
|
• cranial bones are thinner
|
• lower incisors are greatly reduced
|
• since there are no erupted lower incisors, there is continous growth and inward curving of the upper incisors; the teeth force themselves against the palate, cause ulcerations, inanition, and death
|
• crown cusp pattern of the molars is abnormal
|
• all mutants (30 of 30) show absence of at least one third molar
(J:12998)
• most mutants have no third molars at all; only 3 of 30 mutants have just one third molar missing
(J:12998)
• males are more severely affected than females
(J:12998)
• however, upper and lower jaws are almost equally affected, with no differences between right and left
(J:12998)
|
• all molars are significantly reduced in size; however, the greatest size reduction is confined to the third molars which tend to be absent
(J:12998)
• the first molars are moderately reduced while the second molars are considerably reduced in size
(J:12999)
|
• tooth germs that give rise to the third molars reach the cap stage but do not invaginate to form a bell
• regression of the third molars begins earlier and lasts longer, beginning on the 5th day instead of the 6th day in controls
|
• reduced and/or unerupted lower incisors
(J:13045)
|
• molar development is slightly delayed such that at P3, when the enamel organ has reached the bud stage in wild-type, it is still in the early bud stage in mutants; this difference persists up to P8
|
• 4 of 17 mutants have bent noses; the nasals are not aligned with the medial suture of the paired frontals
|
• small mutants have elongate and pointed heads
|
• occasionally small mutants have inclined pinnae
|
limbs/digits/tail
• 95% have abnormal caudal vertebrae
(J:13045)
|
• seen on a rare occasion
(J:13045)
• misshapen or fused vertebrae
(J:101423)
|
• many caudal vertebrae are shortened, some so much that they appear as bone fragments
|
kinked tail
(
J:13045
)
• crooked tail
|
vision/eye
anophthalmia
(
J:13045
)
• occurs sometimes
|
behavior/neurological
• 58% of small mutants exhibit nervous head movement
|
hearing/vestibular/ear
• occasionally small mutants have inclined pinnae
|
respiratory system
• 4 of 17 mutants have bent noses; the nasals are not aligned with the medial suture of the paired frontals
|
embryo
• irregular somites at E14
|
• smaller somites with reduced intervertebral spaces
|
integument
• the coat of some small mutants appears to have an abnormal texture which makes them appear ungroomed
|
• almost naked tail
(J:12999)
• sparse hairs on the tail; the hairs are short and bristle-like
(J:13045)
• coats of some small mutants appears thin
(J:13045)
|
• skin on the tail lacks the proper tail rings
(J:12999)
• small mutants exhibit irregular, discontinuous tail rings
(J:13045)
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
neural tube defect | DOID:0080074 |
OMIM:301410 OMIM:601634 |
J:58433 , J:101423 |