Phenotypes Associated with This Genotype

Genotype
MGI:3784200

• Allelic Composition: Sbf2^Gt(XH212)Byg/Sbf2^Gt(XH212)Byg
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

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

behavior/neurological

limb grasping ( J:132044 )

• mild limb clamping seen starting at 2 months of age

impaired coordination ( J:132044 )

• impaired performance on a rotarod at 12 months but not at 4 months of age

nervous system

abnormal axon morphology ( J:132044 )

• some sciatic nerve fibers without myelin misfoldings show widening of the periaxonal space

abnormal myelin sheath morphology ( J:132044 )

• infoldings and outfoldings of the entire myelin sheath of sciatic nerve fibers are seen by 3 weeks of age and become progressively more numerous and complex with age

• in ventral and dorsal roots misfoldings are seen faintly at 4 months of age and more obviously at 15 months of age

• infoldings present as finger-like inversions of the sheath or circular inclusions within the nerve fiber that may entrain Schwann cell cytoplasm and displace axoplasm

• complex misfoldings are preferentially found in nodal and paranodal regions

• no gross loss of myelinated axons, Schwann cell onion bulb formations, or abnormalities in myelin compaction or periodicity are detected

neuron degeneration ( J:132044 )

• degeneration of whole Scwann cell-axon units in the sciatic nerve are seen sporadically at 4 months and more frequently at 15 months of age

abnormal action potential ( J:132044 )

• reduced compound muscle action potential amplitude in the sciatic nerve at 12 months but not at 4 months of age

• F-wave latency is slightly but not significantly increased

reproductive system

reproductive system phenotype ( J:132044 )

N • unlike mice null for Mtmr2, no signs of impaired spermatogenesis are detected

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Charcot-Marie-Tooth disease type 4B2		DOID:0110190	OMIM:604563	J:133042