Phenotypes associated with this allele

• Allele Symbol: Fgfr2^tm4Lni
• Allele Name: targeted mutation 4, Peter Lonai
• Allele ID: MGI:3053095
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Fgfr2^tm4Lni/Fgfr2^tm4Lni	Not Specified	MGI:3053578
ht2	Fgfr2^tm4Lni/Fgfr2^+	Not Specified	MGI:3053579

Genotype
MGI:3053578

hm1

• Allelic Composition: Fgfr2^tm4Lni/Fgfr2^tm4Lni
• Genetic Background: Not Specified

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

+/+ wildtype, Fgfr2^tm4Lni/Fgfr2^tm4Lni and Fgfr2^tm4Lni/⁺ phenotypic characterizations

cellular

abnormal osteoblast physiology ( J:92433 )

• excessive bone formation is seen in the axial skeleton of newborn homozygous mutants

mortality/aging

neonatal lethality, complete penetrance ( J:92433 )

• homozygotes die shortly after birth with signs of respiratory failure

craniofacial

abnormal basicranium morphology ( J:92433 )

• the skull base is shortened, thickened, and curved

short basicranium ( J:92433 )

abnormal nasal bone morphology ( J:92433 )

• the nasal bones are thickened

abnormal palatine bone morphology ( J:92433 )

• the palatine bones are thickened

domed cranium ( J:92433 )

abnormal palatal shelf fusion at midline ( J:92433 )

• the secondary bony palate fails to close

short face ( J:92433 )

• homozygotes display an extremely shortened face and skull base

cleft secondary palate ( J:92433 )

• the secondary bony palate fails to close with overt cleft palate in 3 out of 4 homozygotes

respiratory system

abnormal nasal bone morphology ( J:92433 )

• the nasal bones are thickened

abnormal lung morphology ( J:92433 )

• the lungs are underdeveloped

fused tracheal cartilage rings ( J:92433 )

• the tracheal cartilage rings are fused into a thin cartilaginous sheet

respiratory failure ( J:92433 )

skeleton

abnormal osteoblast physiology ( J:92433 )

• excessive bone formation is seen in the axial skeleton of newborn homozygous mutants

fused tracheal cartilage rings ( J:92433 )

• the tracheal cartilage rings are fused into a thin cartilaginous sheet

abnormal appendicular skeleton morphology ( J:92433 )

• the knee joint is fused by a posterior bony bridge in most newborn mutants

abnormal axial skeleton morphology ( J:92433 )

• the axial skeleton is shorter and thicker than wild-type littermates

abnormal basicranium morphology ( J:92433 )

• the skull base is shortened, thickened, and curved

short basicranium ( J:92433 )

abnormal nasal bone morphology ( J:92433 )

• the nasal bones are thickened

abnormal palatine bone morphology ( J:92433 )

• the palatine bones are thickened

domed cranium ( J:92433 )

abnormal sternebra morphology ( J:92433 )

• synostosis of the sternebrae (connection of the elements of the sternum by osseous tissue) is seen

vertebral fusion ( J:92433 )

• the lower cervical and upper thoracic and the sacral and caudal vertebrae are fused

increased osteoblast cell number ( J:92433 )

• significantly more osteoblasts are seen in the long bones

abnormal bone ossification ( J:92433 )

• many ossification centers are closer togther than in wild-type mice

vision/eye

eyelids open at birth ( J:92433 )

digestive/alimentary system

abnormal palatal shelf fusion at midline ( J:92433 )

• the secondary bony palate fails to close

cleft secondary palate ( J:92433 )

• the secondary bony palate fails to close with overt cleft palate in 3 out of 4 homozygotes

growth/size/body

abnormal nasal bone morphology ( J:92433 )

• the nasal bones are thickened

abnormal palatal shelf fusion at midline ( J:92433 )

• the secondary bony palate fails to close

short face ( J:92433 )

• homozygotes display an extremely shortened face and skull base

cleft secondary palate ( J:92433 )

• the secondary bony palate fails to close with overt cleft palate in 3 out of 4 homozygotes

Genotype
MGI:3053579

ht2

• Allelic Composition: Fgfr2^tm4Lni/Fgfr2⁺
• Genetic Background: Not Specified

+/+ wildtype and Fgfr2^tm4Lni/⁺ skull phenotypes and histological sections.

craniofacial

abnormal frontal bone morphology ( J:235329 )

• elastic modulus of the frontal bone is lower than in wild-type mice at P10 and P20 and is lower than in parietal bone compared to wild-type mice which show a higher elastic modulus of the frontal bone than the parietal bone

• frontal bone is more porous, showing less trabecular bone and larger lacunae at P10

• however, no difference in the elastic modulus of parietal bone is seen

abnormal sphenoid bone morphology ( J:92433 )

• skull base shortening is mainly in the sphenoid region

• at E14.5 chondrocyte proliferation in the basisphenoid-basioccipital synchondrosis is decreased, however by E16.5 proliferation had returned to normal

decreased molar number ( J:92433 )

• one molar is missing at 4 weeks

malocclusion ( J:92433 )

• a few heterozygotes display a lateral deviation of the nasal area resulting in malocclusion and feeding impairment

short maxilla ( J:92433 )

• at 4 weeks the maxilla is shorter than normal

domed cranium ( J:92433 )

• rounding is the result of shortening on the rostrocaudal axis

short face ( J:92433 )

• heterozygotes display a shortened face

skeleton

abnormal frontal bone morphology ( J:235329 )

• elastic modulus of the frontal bone is lower than in wild-type mice at P10 and P20 and is lower than in parietal bone compared to wild-type mice which show a higher elastic modulus of the frontal bone than the parietal bone

• frontal bone is more porous, showing less trabecular bone and larger lacunae at P10

• however, no difference in the elastic modulus of parietal bone is seen

abnormal sphenoid bone morphology ( J:92433 )

• skull base shortening is mainly in the sphenoid region

• at E14.5 chondrocyte proliferation in the basisphenoid-basioccipital synchondrosis is decreased, however by E16.5 proliferation had returned to normal

decreased molar number ( J:92433 )

• one molar is missing at 4 weeks

malocclusion ( J:92433 )

• a few heterozygotes display a lateral deviation of the nasal area resulting in malocclusion and feeding impairment

short maxilla ( J:92433 )

• at 4 weeks the maxilla is shorter than normal

domed cranium ( J:92433 )

• rounding is the result of shortening on the rostrocaudal axis

increased osteoblast cell number ( J:92433 )

• significantly more osteoblasts are seen in the long bones

premature cranial suture closure ( J:92433 )

• at 4 weeks the coronal sutures are fused, the lamboid sutures partially fused, and the saggital sutures only partially separable

premature coronal suture closure ( J:92433 , J:235329 )

• at E16.5 increased overlap of the frontal and parietal bones (coronal suture) is seen (J:92433)

• at E14.5 increased proliferation of osteoprogenitors is seen in the frontal and parietal bone fronts of the coronal suture, however by E16.5 proliferation had returned to normal (J:92433)

• early fusion of the coronal suture joining the parietal and frontal bone (J:235329)

vision/eye

exophthalmos ( J:92433 )

• protruding eyes are seen

ocular hypertelorism ( J:92433 )

• widely spaced eyes are seen

growth/size/body

decreased molar number ( J:92433 )

• one molar is missing at 4 weeks

malocclusion ( J:92433 )

• a few heterozygotes display a lateral deviation of the nasal area resulting in malocclusion and feeding impairment

short face ( J:92433 )

• heterozygotes display a shortened face

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Crouzon syndrome		DOID:2339	OMIM:123500	J:92433 , J:235329