Phenotypes Associated with This Genotype

Genotype
MGI:2176912

• Allelic Composition: Gjb1^tm1Kwi/Gjb1^tm1Kwi
• Genetic Background: involves: 129S4/SvJae * C57BL/6

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

growth/size/body

decreased body weight ( J:36146 )

♀ • at 7-28 weeks of age, female homozygotes show a ~17% reduction in average body weight relative to wild-type controls

liver/biliary system

abnormal liver morphology ( J:36146 )

♀ • female homozygotes show a ~1000-fold reduction in the total area of gap junctional plaques in the liver relative to wild-type controls

nervous system

nervous system phenotype ( J:36146 )

♀N • young female homozygotes (2-4.5 months of age) show normal mixed afferent and motor nerve conduction in the sciatic nerve and no defects in the refractory periods and motor nerve conduction in the facial nerve relative to age-matched control mice

♀N • no morphologic abnormalities of the myelin sheath are detected in the sciatic nerve at 3 months of age, as determined by electron microscopy

abnormal nervous system morphology ( J:85828 )

♀ • mice develop a demyelinating peripheral neuropathy after 3 months of age

abnormal Schwann cell morphology ( J:85828 )

♀ • onion bulbs, consisting of supernumerary Schwann cells around axons resulting from repeating demyelination and remyelination, develop between 5-12 months of age

♀ • denervated Schwann cells are occasionally observed

♀ • myelinated fibers show an accumulation of adaxonal Schwann cell cytoplasm

abnormal axon morphology ( J:85828 )

♀ • internodes of 9 month old ventral root fibers are shorter and thinner, with abrupt changes in their lengths and myelin thickness along a single fiber

abnormal myelin sheath morphology ( J:85828 )

♀ • remyelinated axons contain thin myelin sheaths

♀ • some incisures appear to be abnormally widened

♀ • nerves exhibit separation of the myelin sheath from the axon

♀ • nerves exhibit splitting of the myelin sheath itself

♀ • central nervous system myelin appears normal

demyelination ( J:85828 )

♀ • demyelinated and remyelinated axons are seen by 3 months of age in motor and sensory branches of the femoral nerve and in the ventral and dorsal roots and in sciatic nerve

♀ • number of demyelinated and remyelinated axons are increased further between 5-12 months of age in femoral and sciatic nerves

♀ • motor fibers in the femoral and sciatic nerves and ventral roots are more affected than sensory fibers and dorsal roots

behavior/neurological

behavior/neurological phenotype ( J:85828 )

♀N • no obvious behavioral abnormalities

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Charcot-Marie-Tooth disease X-linked dominant 1		DOID:0110209	OMIM:302800	J:36146