Phenotypes Associated with This Genotype

Genotype
MGI:3582551

• Allelic Composition: Twist1^Ska10/Twist1^Ska10
• Genetic Background: C57BL/6J-Twist1^Ska10

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

mortality/aging

neonatal lethality, complete penetrance ( J:90056 )

• homozygotes die immediately after birth

limbs/digits/tail

polydactyly ( J:90056 )

• at E16, homozygotes display polydactyly of the hindlimbs

short limbs ( J:90056 )

• at E16, homozygotes have short limbs relative to wild-type mice

skeleton

abnormal osteoblast differentiation ( J:90056 )

• in mutant ribs, accelerated endochondral ossification leads to premature osteoblast differentiation

abnormal clavicle morphology ( J:90056 )

• beginning at E15, homozygotes exhibit a consistently thicker bone collar relative to wild-type mice

abnormal rib morphology ( J:90056 )

• histologically, E15 mutant ribs resemble E16 rather than E15 wild-type ribs; osteocalcin is detected as early as E15 in mutant ribs but remains absent in wild-type E15 and 16 ribs

• at E18, wild-type and mutant ribs are comparable in morphology, although mutant ribs have a thicker bone collar and consistently contain more trabeculae relative to wild-type

abnormal bone ossification ( J:90056 )

• at E16, mutant (but not wild-type) ribs are surrounded by a thick bone collar and contain bone trabeculae in the diaphysis, indicating advanced bone formation

premature endochondral bone ossification ( J:90056 )

• at E14 and E15, mutant ribs show a slight increase in hypertrophic chondrocytes relative to wild-type ribs

• at E16, chondrocyte hypertrophy is markedly increased in wild-type ribs but noticeably reduced in mutant ribs

nervous system

nervous system phenotype ( J:90056 )

N • at E16, homozygotes do NOT display any overt neural tube defects

cellular

abnormal osteoblast differentiation ( J:90056 )

• in mutant ribs, accelerated endochondral ossification leads to premature osteoblast differentiation