Phenotypes Associated with This Genotype

Genotype
MGI:5770597

• Allelic Composition: Runx2^tm1Hkiy/Runx2^tm1Hkiy
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

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

Runx2^tm1Hkiy/Runx2⁺ and Runx2^tm1Hkiy/Runx2^tm1Hkiy mice show delayed bone ossification

mortality/aging

neonatal lethality, complete penetrance ( J:223410 )

• all homozygotes die within 24 hours of birth

skeleton

abnormal neurocranium morphology ( J:223410 )

• significantly delayed formation of the calvaria at E18.5

absent occipital bone ( J:223410 )

• at E18.5

abnormal hyoid bone morphology ( J:223410 )

• complete lack of ossification of hyoid bone at E18.5

abnormal phalanx morphology ( J:223410 )

• absence of some but not all of the ossification centers in the phalanges at E18.5

absent clavicle ( J:223410 )

• complete loss of the clavicle at E18.5

decreased bone mineral density of femur ( J:223410 )

• decreased femoral bone density, as shown by quantitative bone mineral parameters at E18.5

decreased volumetric bone mineral density ( J:223410 )

• at E18.5

decreased bone volume ( J:223410 )

• in femurs at E18.5

decreased bone trabecula number ( J:223410 )

• in femurs at E18.5

increased bone trabecular spacing ( J:223410 )

• significantly increased trabecular separation and spacing in femurs at E18.5

decreased trabecular bone thickness ( J:223410 )

• reduced thickness of trabecula in femurs at E18.5

decreased bone mass ( J:223410 )

• significantly reduced bone mass per tissue volume at E18.5

abnormal skeleton development ( J:223410 )

• hypoplastic skeletal development at E18.5

• delayed formation of the skeleton, most notable in the calvaria

impaired osteoblast differentiation ( J:223410 )

• in vitro, E18.5 calvarial cells cultured in osteogenic medium show defective osteoblast development, as determined by the dramatic reduction in formation of bone nodules relative to wild-type controls

• alkaline phosphatase activity is significantly decreased at the time of bone nodule formation

delayed bone ossification ( J:223410 )

• severely delayed bone ossification at E18.5

delayed endochondral bone ossification ( J:223410 )

• complete lack of ossification of hyoid bone at E18.5

• absence of some but not all of the ossification centers in the phalanges at E18.5

delayed intramembranous bone ossification ( J:223410 )

• significantly delayed formation of the calvaria at E18.5

• intramembranous ossification is more severely affected than endochondral ossification

delayed sagittal suture closure ( J:223410 )

• closure of the sagittal suture is severely delayed at E18.5

craniofacial

abnormal neurocranium morphology ( J:223410 )

• significantly delayed formation of the calvaria at E18.5

absent occipital bone ( J:223410 )

• at E18.5

abnormal hyoid bone morphology ( J:223410 )

• complete lack of ossification of hyoid bone at E18.5

limbs/digits/tail

abnormal phalanx morphology ( J:223410 )

• absence of some but not all of the ossification centers in the phalanges at E18.5

cellular

impaired osteoblast differentiation ( J:223410 )

• in vitro, E18.5 calvarial cells cultured in osteogenic medium show defective osteoblast development, as determined by the dramatic reduction in formation of bone nodules relative to wild-type controls

• alkaline phosphatase activity is significantly decreased at the time of bone nodule formation