Mouse Genome Informatics
ht
    Fgfr3tm1.1Iwa/Fgfr3+
involves: 129S6/SvEvTac * FVB/N * NIH Black Swiss
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
       
mortality/aging
• one set of mutants (52%) that are very small, die 4 weeks after birth
• 24% of mildly affected mutants live longer than 3 months, including some up to as long as wild-type
• Background Sensitivity: on a CD background, about 46% that are severely affected die early while 14% live longer than 3 months

growth/size/body
• distinguishable at birth by a mildly round head
• those that die 4 weeks after birth are very small

craniofacial
• enlarged hyoid bone
• seen in severely affected mice, although some several severely affected mice die without malocclusion

limbs/digits/tail
• shorter limbs with particularly shortened ossified zone

skeleton
• enlarged hyoid bone
• seen in severely affected mice, although some several severely affected mice die without malocclusion
• wider and shorter limb long bones
• delay in sternabrae ossification at P1
• thickening and slight bifurcation of the costal cartilage is seen at P1 and at 15 months of age
• at 15 months of age, observe clonal proliferation of chondrocytes in costal cartilage
• thinner layer of perichondrium in costal cartilage
• smaller rib cage is evident after P4
• exhibit curvature of the axial skeleton
• decrease in chondrocyte differentiation
• exhibit abnormal chondrocyte proliferation, with increased proliferation during embryo development but decreased proliferation in the postnatal growth plate chondrocytes
• chondrocytes in the medial part of the femur are smaller and premature at E15.5
• chondrocytes around the blood vessel in epiphysis are smaller at P4
• overgrowth of hyaline cartilage, including the trachea and the nasal septa and hypertrophy of the thyroid, cricoid, and tracheal cartilages
• growth plates at the junctions of the rib-bone and the costal cartilage at P17 are abnormal
• exhibit ingrowth of mesenchymal tissue across the physis at P17
• some undifferentiated chondrocytes intermingle with the hypertrophic chondrocytes at E15.5
• thicker growth plate with shorter hypertrophic zones and proliferating columns at P17
• chondrocytes have shorter columnar structures of the proliferating zone
• hypertrophic chondrocytes are sparse and not fully mature
• delay formation of the secondary ossification center
• delay in sternabrae ossification at P1

Mouse Models of Human Disease
OMIM IDRef(s)
Achondroplasia; ACH 100800 J:70061