Phenotypes Associated with This Genotype

Genotype
MGI:2653547

• Allelic Composition: Tg(Mpz)80.2Wra/0
• Genetic Background: involves: FVB/N

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

mortality/aging

premature death ( J:78758 )

• median life span is 4 months

homeostasis/metabolism

increased collagen level ( J:78758 )

• collagen is increased within the perineurial compartment

behavior/neurological

tremors ( J:78758 )

decreased grip strength ( J:78758 )

• weak grip strength

abnormal gait ( J:78758 )

• wobbling gait

growth/size/body

decreased body weight ( J:78758 )

muscle

muscular atrophy ( J:78758 )

• atrophy of the paraspinal and hindlimb musculature

• leg muscles exhibit angulated and atrophic fibers suggestive of denervation

nervous system

abnormal nervous system development ( J:78758 )

• nerve development is arrested at the stage in which Schwann cells are segregating large axons away from bundles of mixed caliber axons

abnormal axon radial sorting ( J:78758 )

• Schwann cells incompletely retract their processes after segregation of large axons

• axon-sorting defect is more evident at P5 and P14 than at P28 and even at P45 and P90, some bundles of unsorted larger diameter axons remain indicating delayed axonal sorting

abnormal myelin sheath morphology ( J:78758 )

• sciatic nerve shows a mixture of fibers with thin myelin sheaths for the diameter of axon and fibers in which single Schwann cells ensheath axons, but form no myelin

dysmyelination ( J:78758 )

• mice exhibit severe dysmyelination that results from developmental delay and not myelin destruction

• sciatic nerves at P5 and P14 contain virtually no myelin while occasional patches of myelination fibers are seen at P28 and more frequently at P42

• sciatic nerves show a mixture of fibers with thin myelin sheaths and fibers in which single Schwann cells ensheath axons but form no myelin

• by P10, less than 1% of axons in the motor branch (quadriceps) of developing femoral nerve in 1:1 relationships with Schwann cells are myelinated compared to 100% in wild-type

• the motor branch (quadriceps) is more dysmyelinated than the sensory branch (saphenous) of femoral nerve by P10

• ventral roots are more dysmyelinated than dorsal root

decreased nerve conduction velocity ( J:78758 )

• nerve conduction velocities are reduced to about 2 m/s with temporal dispersion of the compound motor action potential, suggesting dysmyelinating neuropathy

reproductive system

infertility ( J:78758 )

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
neuropathy		DOID:870		J:78758