Phenotypes Associated with This Genotype

Genotype
MGI:3836731

• Allelic Composition: Egr2^tm2Jmi/Egr2^tm2Jmi
• Genetic Background: B6.Cg-Egr2^tm2Jmi

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

mortality/aging

postnatal lethality, complete penetrance ( J:145949 )

• mice die between P18 and P21

nervous system

abnormal Schwann cell morphology ( J:145949 )

• at P14, Schwann cell nuclei are irregularly shaped

• Schwann cells do not progress beyond the promyelinating phase and continue to proliferate unlike wild-type cells

abnormal neuromuscular synapse morphology ( J:145949 )

• at P18, mice exhibit extensive sprouting at the neuromuscular junctions unlike in wild-type mice

• however, no abnormal sprouting is observed at P14

fusion of glossopharyngeal and vagus nerve ( J:145949 )

• in 39% of mice

abnormal sciatic nerve morphology ( J:145949 )

• the nodal structure of the sciatic nerve is abnormal

abnormal myelination ( J:145949 )

• at P14, the number of myelinating profiles is decreased, large caliber axons have no myelin sheaths, and myelin sheaths observed are thinner than in wild-type mice

• however, there is no evidence of demyelination or remyelination

decreased nerve conduction velocity ( J:145949 )

• between P18 and P21 with evidence of conduction block

behavior/neurological

tremors ( J:145949 )

• mild at P14

weakness ( J:145949 )

• mice exhibit weakness in the hindlimbs at P14 and weakness in the forelimbs at P18 unlike wild-type mice

abnormal gait ( J:145949 )

• at P14, mice exhibit slowness and gait abnormality unlike wild-type mice

hindlimb paralysis ( J:145949 )

• within 4 to 7 days of P14 mice exhibit weakness leading to hindlimb paralysis unlike wild-type mice

growth/size/body

weight loss ( J:145949 )

• after P14

respiratory system

respiratory distress ( J:145949 )

• at P18

integument

integument phenotype ( J:145949 )

N • skin histology is normal

cellular

abnormal Schwann cell morphology ( J:145949 )

• at P14, Schwann cell nuclei are irregularly shaped

• Schwann cells do not progress beyond the promyelinating phase and continue to proliferate unlike wild-type cells

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Charcot-Marie-Tooth disease type 4E		DOID:0110195	OMIM:605253	J:145949