Phenotypes Associated with This Genotype

Genotype
MGI:6343572

• Allelic Composition: Gt(ROSA)26Sor^{tm1.1(CAG-SPAST*C448Y)Baas}/Gt(ROSA)26Sor⁺
• Genetic Background: involves: C57BL/6N

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

behavior/neurological

limb grasping ( J:273408 )

♂ • 72% of mice exhibit decreased splay angles of hindlimb limbs when lifted by the tail compared to 33% of wild-type mice, with earlier onset of 73 days compared to 140 days of age in wild-type mice

tremors ( J:273408 )

♂ • 100% of mice exhibit resting tremor at 247 days of age compared to 6.7% of wild-type mice, with onset at 70 days of age

abnormal gait ( J:273408 )

• mice exhibit deficits in gripping the beam in the beam walk assay indicating impaired gait

• females show less severe motor defects than males

growth/size/body

weight loss ( J:273408 )

♂ • a decrease in weight is seen in mice older than P150

nervous system

abnormal corticospinal tract morphology ( J:273408 )

♂ • dorsal and ventral columns show decreased numbers of regular axons and increased numbers of irregular axons, indicating axonal dieback and corticospinal degeneration

abnormal axon morphology ( J:273408 )

♂ • dorsal and ventral columns show decreased numbers of regular axons and increased numbers of irregular axons, indicative of axonal dieback

abnormal spinal cord morphology ( J:273408 )

♂ • spinal cord, particularly the lower spinal cord, exhibits a reduction in microtubule stability

axon degeneration ( J:273408 )

♂ • progressive axonal degeneration in the dorsal column

abnormal axonal transport ( J:273408 )

♂ • cortical neurons from P0 mice show a decrease in retrograde movements of axonal lysosomes, with an increase in movements that are halted or stationary

♂ • however, no instantaneous velocity differences in lysosomal movement are seen

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
hereditary spastic paraplegia 4		DOID:0110792	OMIM:182601	J:273408