Phenotypes Associated with This Genotype

Genotype
MGI:4417874

• Allelic Composition: Comp^tm1Mbri/Comp^tm1Mbri
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ

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

muscle

centrally nucleated skeletal muscle fibers ( J:154984 )

• at 3 weeks, 33% of muscle fibers exhibit centrally localized nuclei unlike in wild-type mice

• centrally located nuclei are present at myotendinous junction and around the perimysium unlike in wild-type mice

• at 6 weeks, the number of muscle fibers with centrally located nuclei is more than 2.5-fold greater than in wild-type mice

abnormal tendon morphology ( J:154984 )

• at 3 and 9 weeks, the distribution of collagen fibril diameters in the Achilles tendon is altered compared to in wild-type mice

• at 3 weeks, the total number of collage fibers in the Achilles tendon are reduced compared to in wild-type mice

• at 3 weeks, more fused or bifurcating and thinner collagen fibrils are found in the Achilles tendon compared to in wild-type mice

• however, endoplasmic reticulum stress and apoptosis is not increased in tenocytes

decreased tendon stiffness ( J:154984 )

• the Achilles tendon is more lax than wild-type tendons in biomechanical testing

increased muscle fatigability ( J:154984 )

• at 3 weeks, mice exhibit a 12.6% decrease in grip release strength compared with wild-type mice

• at 9 weeks, maximum grip strength and release force is lower than in wild-type mice

myopathy ( J:154984 )

• mild

behavior/neurological

decreased grip strength ( J:154984 )

• at 9 weeks, maximum grip strength and release force is lower than in wild-type mice

skeleton

abnormal tendon morphology ( J:154984 )

• at 3 and 9 weeks, the distribution of collagen fibril diameters in the Achilles tendon is altered compared to in wild-type mice

• at 3 weeks, the total number of collage fibers in the Achilles tendon are reduced compared to in wild-type mice

• at 3 weeks, more fused or bifurcating and thinner collagen fibrils are found in the Achilles tendon compared to in wild-type mice

• however, endoplasmic reticulum stress and apoptosis is not increased in tenocytes

decreased tendon stiffness ( J:154984 )

• the Achilles tendon is more lax than wild-type tendons in biomechanical testing

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
multiple epiphyseal dysplasia		DOID:12721		J:154984