Phenotypes associated with this allele

• Allele Symbol: Chrm1^tm1Nmn
• Allele Name: targeted mutation 1, Neil M Nathanson
• Allele ID: MGI:2158709
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Chrm1^tm1Nmn/Chrm1^tm1Nmn	B6.129X1-Chrm1^tm1Nmn	MGI:3695762

Genotype
MGI:3695762

hm1

• Allelic Composition: Chrm1^tm1Nmn/Chrm1^tm1Nmn
• Genetic Background: B6.129X1-Chrm1^tm1Nmn

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

nervous system

abnormal auditory cortex morphology ( J:96239 )

• at 6-8 weeks of age, homozygotes display a grossly normal architecture in all six layers of the auditory cortex, with no differences in total dendrite length of layer V pyramidal neurons

• however, the dendritic arborization of layer IV multi-polar granular neurons is markedly reduced, with dendrites being shorter and sparser than normal, suggesting a deficit in thalamocortical innervation or synapse formation

abnormal auditory cortex tonotopy ( J:96239 )

• at 6-8 weeks of age, homozygotes display disorganized frequency maps (tonotopy) of the auditory cortex due to deficits in frequency tuning of cortical neurons and impaired cytoarchitecture in layer IV of the auditory cortex

• in contrast, tonotopic organization and frequency tuning in the auditory midbrain is normal

abnormal CNS synapse formation ( J:96239 )

• the dendritic arborization of layer IV multi-polar granular neurons is markedly reduced, suggesting impaired synapse formation

hearing/vestibular/ear

hearing/vestibular/ear phenotype ( J:96239 )

N • at 6-8 weeks of age, homozygotes exhibit normal hearing sensitivity, with similar auditory brainstem response (ABR) thresholds across various frequencies ranging from 3 to 36 kHz relative to wild-type mice