Phenotypes associated with this allele

• Allele Symbol: Abr^tm1Jhg
• Allele Name: targeted mutation 1, John H Groffen
• Allele ID: MGI:2388713
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Abr^tm1Jhg/Abr^tm1Jhg	involves: 129S1/Sv * 129X1/SvJ * Black Swiss	MGI:2671968
cx2	Abr^tm1Jhg/Abr^tm1Jhg Bcr^tm1Hkp/Bcr^tm1Hkp	involves: 129S1/Sv * 129S2/SvPas * 129X1/SvJ * Black Swiss * C57BL/6	MGI:2653904

Genotype
MGI:2671968

hm1

• Allelic Composition: Abr^tm1Jhg/Abr^tm1Jhg
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * Black Swiss

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

normal phenotype

no abnormal phenotype detected ( J:72425 )

Genotype
MGI:2653904

cx2

• Allelic Composition: Abr^tm1Jhg/Abr^tm1Jhg; Bcr^tm1Hkp/Bcr^tm1Hkp
• Genetic Background: involves: 129S1/Sv * 129S2/SvPas * 129X1/SvJ * Black Swiss * C57BL/6

mortality/aging

neonatal lethality, incomplete penetrance ( J:72425 )

• the expected numbers of mutants are seen immediately after birth, however a reduced frequency is seen one day after birth

behavior/neurological

impaired balance ( J:108010 )

• mutants frequently lose their balance

impaired coordination ( J:72425 , J:108010 )

• clumsy movement, stumbling (J:72425)

• poor motor coordination (J:108010)

impaired swimming ( J:108010 )

• unable to swim

hyperactivity ( J:72425 , J:108010 )

circling ( J:72425 , J:108010 )

nervous system

abnormal cerebellum morphology ( J:72425 )

abnormal cerebellar foliation ( J:72425 )

• defective foliation is seen as early as P11, with abnormal anterior foliation pattern including partial fusion

ectopic cerebellar granule cells ( J:72425 )

• large numbers of granule neurons are found in an abnormal location on the surface of the molecular layer of the cerebellum

• ectopic granule cells are found in all folia, but numbers are especially high in the anterior folia of the cerebellar vermis and anterior medullary velum

abnormal CNS glial cell morphology ( J:72425 )

• spontaneous glial hypertrophy

• premature termination and disorganization of the end-feet of the Bergmann fibers

abnormal radial glial cell morphology ( J:72425 )

• disorganization of radial glia on the cerebellar cortex at P5

abnormal astrocyte morphology ( J:72425 )

• mutants display aberrant Gfap-positive astroglia on the surface of the cerebellar external granule layer at P5; glial processes often lose their radial orientation when they approach the pial surface and display abnormal end-feet, that fail to form a well-defined glial boundary

• serum starved astrocytes are 20% more spread than control cells and upon epidermal growth factor stimulation, mutant cells project distinct Gfap-positive protrusions not seen in controls

gliosis ( J:72425 )

• reactive gliosis in the midbrain in response to kainic acid exposure

abnormal astrocyte physiology ( J:72425 )

• astroglia are hyperresponsive to stimulation with epidermal growth factor and lipopolysaccharide

hearing/vestibular/ear

hearing/vestibular/ear phenotype ( J:108010 )

N • mutants are not deaf as they respond to the Preyer reflex test at 1 year of age and exhibit normal cochlea, semicircular canals, organ of Corti, and vestibular ganglia and nerves

abnormal inner ear development ( J:108010 )

• vacuolation is seen under or within the utricular and saccular epithelium at E13.5, indicating abnormal vestibular development

abnormal inner ear vestibule morphology ( J:108010 )

• dysplasia of the vestibular compartment of the inner ear

• reduction in the sensory epithelium in both the saccule and the utricle

abnormal utricle morphology ( J:108010 )

• utricle is grossly abnormal

abnormal vestibular saccule morphology ( J:108010 )

• vacuolation is seen on both sides of the saccular epithelium at 3 weeks of age

• saccule is grossly malformed, showing detachment of the epithelial layer from the underlying connective tissue

decreased otolith number ( J:108010 )

• otoconia are either missing or reduced in number in the saccule

absent otoliths ( J:72425 , J:108010 )

• absence of vestibular otoconia (J:72425)

• total loss of otoconia in the utricle (J:108010)

• otoconia are either missiong or reduced in number in the saccule (J:108010)

enlarged otoliths ( J:108010 )

• when present in the saccule, otoconia are abnormally large

cellular

abnormal radial glial cell morphology ( J:72425 )

• disorganization of radial glia on the cerebellar cortex at P5