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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID 		Cacnb2tm1Rgg
targeted mutation 1, Ronald G Gregg
MGI:2429694
Summary 3 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
 		Cacnb2tm1Rgg/Cacnb2tm1Rgg involves: 129S7/SvEvBrd MGI:3843805
hm2
 		Cacnb2tm1Rgg/Cacnb2tm1Rgg involves: 129S7/SvEvBrd * FVB MGI:3797409
cx3
 		Cacnb2tm1Rgg/Cacnb2tm1Rgg
Pde6brd1/Pde6brd1
Tg(Myh6-Cacnb2)1Rgg/0 		involves: 129S7/SvEvBrd * C57BL/6J * FVB MGI:2451250


Genotype
MGI:3843805
hm1
Allelic
Composition		 Cacnb2tm1Rgg/Cacnb2tm1Rgg
Genetic
Background		 involves: 129S7/SvEvBrd
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Cacnb2tm1Rgg mutation (0 available); any Cacnb2 mutation (48 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
mortality/aging
embryonic lethality, complete penetrance ( J:80080 )
• homozygous mice die during embryogenesis due to failure of cardiac contraction

cardiovascular system
abnormal cardiovascular system physiology ( J:80080 )
• failure of cardiac contraction during embryogenesis




Genotype
MGI:3797409
hm2
Allelic
Composition		 Cacnb2tm1Rgg/Cacnb2tm1Rgg
Genetic
Background		 involves: 129S7/SvEvBrd * FVB
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Cacnb2tm1Rgg mutation (0 available); any Cacnb2 mutation (48 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
vision/eye
vision/eye phenotype ( J:136113 )
N
• mice exhibit normal electroretinograms




Genotype
MGI:2451250
cx3
Allelic
Composition		 Cacnb2tm1Rgg/Cacnb2tm1Rgg
Pde6brd1/Pde6brd1
Tg(Myh6-Cacnb2)1Rgg/0
Genetic
Background		 involves: 129S7/SvEvBrd * C57BL/6J * FVB
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Cacnb2tm1Rgg mutation (0 available); any Cacnb2 mutation (48 available)
Pde6brd1 mutation (39 available); any Pde6b mutation (123 available)
Tg(Myh6-Cacnb2)1Rgg mutation (0 available)
♀ phenotype observed in females
♂ phenotype observed in males
N normal phenotype
vision/eye
decreased retina photoreceptor cell number ( J:79923 )
• progressive loss of photoreceptor cell bodies
• increased apoptotic cell death at 21 days of age
retina photoreceptor degeneration ( J:79923 )
• degeneration of photoreceptors occurs but is delayed at P16, P18, and P21 compared to homozygous Pde6b mutants
thin retina outer nuclear layer ( J:79923 )
• progressive thinning of the outer nuclear layer
disorganized retina outer plexiform layer ( J:80080 )
• the OPL appears disorganized
thin retina outer plexiform layer ( J:80080 )
• the OPL appears thinner than wild-type and other controls
abnormal eye physiology ( J:80080 )
• mutant mice show decreased sensitivity to light
abnormal eye electrophysiology ( J:80080 )
• the b-wave of mutant mice is reduced in amplitude at all flash intensities; the a-wave appears similar to controls
abnormal cone electrophysiology ( J:80080 )
• cone ERGs of mutant mice are smaller in amplitude and negative in polarity

nervous system
decreased retina photoreceptor cell number ( J:79923 )
• progressive loss of photoreceptor cell bodies
• increased apoptotic cell death at 21 days of age
retina photoreceptor degeneration ( J:79923 )
• degeneration of photoreceptors occurs but is delayed at P16, P18, and P21 compared to homozygous Pde6b mutants




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Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
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Send questions and comments to User Support. 		last database update
09/30/2025
MGI 6.24 		The Jackson Laboratory