Phenotypes Associated with This Genotype

Genotype
MGI:5779551

• Allelic Composition: Tg(PMP22-tTA)JY13Clh/0; Tg(tetO/CMV-Pmp22)JP18Clh/0
• Genetic Background: involves: C57BL/6J * CBA/Ca

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

behavior/neurological

abnormal gait ( J:69545 )

• slightly abnormal gait

nervous system

increased Schwann cell number ( J:69545 )

decreased myelin sheath thickness ( J:69545 )

• 26% of axons within the sciatic nerve exhibit very thin or absent myelin

• mice fed tetracycline at 8 weeks of age to turn off transgene expression show myelination of non-myelinated fibers within 1 week of tetracycline feeding, however myelin sheaths of these fibers are still very thin by 2 weeks of feeding

• mice fed tetracycline at 8 weeks of age for 4-12 weeks show a dramatic decrease in the percentage of very thinly myelinated fibers, however the myelin sill has not reached normal thickness

abnormal myelination ( J:69545 )

• a proportion of axons in 16 week old mice (particularly medium and smaller sized axons) have very thin or no myelin

• mice administered tetracycline from at least a week before birth to turn off transgene expression exhibit nearly normal myelin thickness at 16 weeks of age and only about 1% of axons show very thin or absent myelin

• mice fed tetracycline from before birth to 8 weeks of age develop nearly normal mature myelin

demyelination ( J:69545 )

• mice fed tetracycline from before birth to 8 weeks of age at which age tetracycline was removed to turn on transgene expression show some demyelination such that after 8 weeks of expression, 9% of fibers are demyelinated

decreased nerve conduction velocity ( J:69545 )

• motor nerve conduction velocity in the sciatic/tibial nerves is slightly reduced

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Charcot-Marie-Tooth disease type 1A		DOID:0110148	OMIM:118220	J:69545