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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID
Chrna7tm1Bay
targeted mutation 1, Baylor College of Medicine
MGI:1888407
Summary 11 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
Chrna7tm1Bay/Chrna7tm1Bay B6.129S7-Chrna7tm1Bay/J MGI:3819267
hm2
Chrna7tm1Bay/Chrna7tm1Bay B6.Cg-Chrna7tm1Bay MGI:3050969
hm3
Chrna7tm1Bay/Chrna7tm1Bay involves: 129S7/SvEvBrd MGI:4462395
hm4
Chrna7tm1Bay/Chrna7tm1Bay involves: 129S7/SvEvBrd * C3H/HeN MGI:5603931
hm5
Chrna7tm1Bay/Chrna7tm1Bay involves: 129S7/SvEvBrd * C57BL/6 MGI:4950023
hm6
Chrna7tm1Bay/Chrna7tm1Bay involves: 129S7/SvEvBrd * C57BL/6J MGI:3050953
ht7
Chrna7tm1Bay/Chrna7+ B6.129S7-Chrna7tm1Bay/J MGI:5603929
ht8
Chrna7tm1Bay/Chrna7+ involves: 129S7/SvEvBrd * C3H/HeN MGI:5603932
cx9
Chrna3tm1.1Hwrt/Chrna3tm1.1Hwrt
Chrna7tm1Bay/Chrna7tm1Bay
involves: 129S1/Sv * 129S7/SvEvBrd * C57BL/6 MGI:4442219
cx10
Agrntm4Jrs/Agrntm4Jrs
Chrna1tm1Klee/Chrna1tm1Klee
Chrna7tm1Bay/Chrna7tm1Bay
involves: 129S4/SvJae * 129S7/SvEvBrd * C57BL/6 MGI:4462396
cx11
Chrna7tm1Bay/Chrna7tm1Bay
Chrnb2tm1Mdb/Chrnb2tm1Mdb
involves: 129S7/SvEvBrd * C57BL/6J MGI:4822560


Genotype
MGI:3819267
hm1
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
B6.129S7-Chrna7tm1Bay/J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
N
• female homozygotes have normal ovaries and enter puberty at the expected age, with no significant differences in the onset of vaginal opening or cornification relative to wild-type or heterozygous control females (J:92540)
• male homozygotes are fertile and exhibit an apparently normal mating behavior (J:92540)
• testicular weight, total sperm number, and sperm morphology appear normal (J:115434)
• mutant sperm initially appear to swim normally but fail to maintain progressive forward motility
• only few mutant sperm retain rapid swimming velocities and display hyperactivated swimming patterns following in vitro capacitation
• many nonmotile sperm exhibit a quivering head and midpiece but no forward movement, confirming that cells are alive
• however, no significant differences in sperm viability, senescence rate or spontaneous acrosome reaction rate are observed between mutant and wild-type sperm before and after capacitation
• female homozygotes show asynchronous, prolonged estrous cycles, with an average cycle length of 7.1 0.68 days relative to wild-type and heterozygous females (4.3 0.19 and 4.3 0.10 days, respectively)
• the extent of asynchrony is variable within the mutant female population, but for a given animal, the average cycle length tends to remain stable at young mature ages (4-6 months) and middle ages (10-14 months)
• all female homozygotes eventually complete an estrous cycle, and may achieve pregnancy but with a smaller number of surviving pups
• the number of live births is significantly less from matings of female homozygotes with either heterozygous (4.5 2.12) or homozygous (3.7 0.53) mutant males in comparison to matings of heterozygous females and males (7.34 0.04) and matings of heterozygous females and homozygous mutant males (7.1 0.40)
• litters born to homozygous mutant females are significantly smaller than those born to heterozygous females regardless of the male genotype

nervous system
• development of parvalbumin-positive GABAergic interneurons is disrupted in cortical cultures
• NMDA receptor expression is reduced in cortical GABAergic interneurons of cortical cultures
• development and maturation of cortical parvalbumin-positive basket cells is impaired in cortical cultures
• parvalbumin and GAD67 levels are reduced in the soma of parvalbumin-positive GABAergic interneurons
• GABAAalpha1 levels are reduced in parvalbumin-positive GABAergic interneurons in the prefrontal cortex
• cortical levels of GABAergic makers (parvalbumin, glutamic acid decarboxylase 65/67 (GAD65/67) and the alpha1 subunit of GABAA receptors) are decreased during late postnatal development and adulthood
• GABAAalpha1 levels are reduced in pyramidal neurons of the prefrontal cortex
• marker analysis indicates that cortical GABAergic synapse formation is impaired in prefrontal cortex and in cortical cultures
• formation of parvalbumin- and GAD65-positive perisomatic synapses is impaired in cortical cultures
• levels of markers of GABAergic maturation are reduced in the neocortex indicating that cortical parvalbumin GABAergic development is impaired
• cortical GABAergic synaptic defects in the prefrontal cortex and in cortical cultures
• cultured cortical pyramidal neurons show a reduction in sIPSC frequency and current decay time, but not amplitude, indicating reduced GABAergic neurotransmission

behavior/neurological
• in the delayed matching-to-place task of the Morris water maze, mutants take longer to find the hidden platform than controls, indicating a minor impairment in working/episodic memory
• however, mice show normal latency to enter the central zone of the open field, normal elevated plus maze behavior, and no differences in swim speed or thigmotaxic behavior

taste/olfaction
• mice exhibit deficits in detecting or discriminating chemically-related odors

cellular
• mutant sperm initially appear to swim normally but fail to maintain progressive forward motility
• only few mutant sperm retain rapid swimming velocities and display hyperactivated swimming patterns following in vitro capacitation
• many nonmotile sperm exhibit a quivering head and midpiece but no forward movement, confirming that cells are alive
• however, no significant differences in sperm viability, senescence rate or spontaneous acrosome reaction rate are observed between mutant and wild-type sperm before and after capacitation

Mouse Models of Human Disease
DO ID OMIM ID(s) Ref(s)
schizophrenia DOID:5419 OMIM:181500
J:214099




Genotype
MGI:3050969
hm2
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
B6.Cg-Chrna7tm1Bay
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
behavior/neurological
N
• homozygotes exhibit normal base-line learning and memory performance, and normal sensorimotor gating relative to wild-type
• also, homozygotes are behaviorally similar to wild-type mice in a wide variety of behavioral tests
• significant gender differences are noted in several tests; however, there is no evidence suggesting that these gender differences are genotype-specific
• homozygotes and wild-type mice display a similar dose-response curve for nicotine-elicited clonic-tonic seizures
• neither cholinergic compensatory mechanisms nor alterations in binding levels or affinity for nicotinic ligands, such as epibatidine or nicotine, can account for the retained sensitivity to the convulsant effects of nicotine
• homozygotes locate the hidden platform in the Morris water task significantly faster than wild-type; however, this is a subtle difference and is not supported by the distance traveled data
• also, homozygotes and wild-type mice show a comparable search behavior during the probe trials
• homozygotes spend a significantly greater proportion of their total distance traveled in the open field in the center of the arena relative to wild-type
• however, this difference in altered anxiety-related behavioral response is not corroborated by the light<->dark exploration test

immune system
• endotoxemic homozygotes produce significantly higher levels of IL-1 and IL-6
• following endotoxin administration, homozygotes show significantly higher levels of serum TNF levels as well as higher TNF production in the liver and spleen relative to wild-type
• mutant macrophages are refractory to cholinergic agonists and generate TNF normally in the presence of nicotine or acetylcholine
• electrical stimulation of the vagus nerve inhibits endotoxin-induced serum TNF levels in wild-type mice, but fails to reduce serum TNF levels in endotoxemic homozygotes

nervous system
• homozygotes and wild-type mice display a similar dose-response curve for nicotine-elicited clonic-tonic seizures
• neither cholinergic compensatory mechanisms nor alterations in binding levels or affinity for nicotinic ligands, such as epibatidine or nicotine, can account for the retained sensitivity to the convulsant effects of nicotine

homeostasis/metabolism
• endotoxemic homozygotes produce significantly higher levels of IL-1 and IL-6
• following endotoxin administration, homozygotes show significantly higher levels of serum TNF levels as well as higher TNF production in the liver and spleen relative to wild-type
• mutant macrophages are refractory to cholinergic agonists and generate TNF normally in the presence of nicotine or acetylcholine
• electrical stimulation of the vagus nerve inhibits endotoxin-induced serum TNF levels in wild-type mice, but fails to reduce serum TNF levels in endotoxemic homozygotes




Genotype
MGI:4462395
hm3
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S7/SvEvBrd
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
nervous system




Genotype
MGI:5603931
hm4
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S7/SvEvBrd * C3H/HeN
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
taste/olfaction
• mice exhibit deficits in detecting or discriminating chemically-related odors




Genotype
MGI:4950023
hm5
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S7/SvEvBrd * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
respiratory system
• after polidocanol-induced acute injury, 8-wk old mutant mice display delayed regeneration of the tracheal epithelium with a transient hyperplasia of basal cells observed on days 4 and 6, but not on day 8, after injury
• at 1 year of age, the % of 1-2 layers of basal cells in the tracheal epithelium is reduced whereas the % of 3-4 layers of basal cells in increased by 3.8-fold relative to that in wild-type controls

cellular
• after polidocanol-induced acute injury, 8-wk old mutant mice display delayed regeneration of the tracheal epithelium with a transient hyperplasia of basal cells observed on days 4 and 6, but not on day 8, after injury

immune system
N
• IgM levels of preimmune serum are little altered from control levels
• significantly reduced preimmune serum Ig levels

hematopoietic system
• significantly reduced preimmune serum Ig levels




Genotype
MGI:3050953
hm6
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S7/SvEvBrd * C57BL/6J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
nervous system
N
• homozygotes display normal growth, survival, gait, and anatomy and show no developmental abnormalities in the nervous system
• homozygotes lack high-affinity [125I]alpha-bungarotoxin binding sites
• however, autoradiography with [3H]nicotine revealed normal levels of high-affinity nicotine binding
• hippocampal neurons from mutant mice do not exhibit rapidly desensitizing, methyllycaconitine-sensitive nicotinic currents

reproductive system
• homozygotes do not breed well

hematopoietic system
• fewer myeloblasts and metamyeloblasts in bone marrow
• fewer erythroblasts and pro-normoblasts found in bone marrow
• fewer band neutrophils in bone marrow
• increased lymphocytes in bone marrow

immune system
• fewer band neutrophils in bone marrow
• increased lymphocytes in bone marrow




Genotype
MGI:5603929
ht7
Allelic
Composition
Chrna7tm1Bay/Chrna7+
Genetic
Background
B6.129S7-Chrna7tm1Bay/J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
taste/olfaction
• mice exhibit deficits in detecting or discriminating chemically-related odors




Genotype
MGI:5603932
ht8
Allelic
Composition
Chrna7tm1Bay/Chrna7+
Genetic
Background
involves: 129S7/SvEvBrd * C3H/HeN
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
taste/olfaction
• mice exhibit deficits in detecting or discriminating chemically-related odors




Genotype
MGI:4442219
cx9
Allelic
Composition
Chrna3tm1.1Hwrt/Chrna3tm1.1Hwrt
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S1/Sv * 129S7/SvEvBrd * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna3tm1.1Hwrt mutation (1 available); any Chrna3 mutation (32 available)
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
nervous system
• most nerve-evoked excitatory postpynaptic potentials (EPSPs) on sympathetic neurons in the superior cervical ganglia are subthreshold compared to in wild-type mice
• unlike in wild-type mice, nerve evoked EPSPs are blocked by alpha-bungarotoxin




Genotype
MGI:4462396
cx10
Allelic
Composition
Agrntm4Jrs/Agrntm4Jrs
Chrna1tm1Klee/Chrna1tm1Klee
Chrna7tm1Bay/Chrna7tm1Bay
Genetic
Background
involves: 129S4/SvJae * 129S7/SvEvBrd * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Agrntm4Jrs mutation (0 available); any Agrn mutation (101 available)
Chrna1tm1Klee mutation (0 available); any Chrna1 mutation (17 available)
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
nervous system




Genotype
MGI:4822560
cx11
Allelic
Composition
Chrna7tm1Bay/Chrna7tm1Bay
Chrnb2tm1Mdb/Chrnb2tm1Mdb
Genetic
Background
involves: 129S7/SvEvBrd * C57BL/6J
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Chrna7tm1Bay mutation (1 available); any Chrna7 mutation (49 available)
Chrnb2tm1Mdb mutation (1 available); any Chrnb2 mutation (32 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
behavior/neurological
N
• mutant and control mice have similar rates of locomotor movement in the open field test; they also display similar levels of exploration of the "anxiety-provoking" area of the open-field indicating that both genotypes show similar anxiety-related responses
• vertical movement, i.e. rearing behavior, is also not significantly different between mutant and control mice
• no differences in prepulse inhibition of the acoustic startle response are detected between mutant and control mice
• compared to controls, mutant mice show significantly decreased latencies to enter the dark side of a light/dark box in a passive avoidance test after an initial shock on the dark side; an increase in shock intensity did not alter the results significantly suggesting that mutant mice do not have a decreased sensitivity to the shock
• in contrast to the open field test, mutant mice show significantly more light-dark transitions in a light/dark crossing task compared with the controls, suggesting decreased anxiety; however, the latency to enter the dark side is similar to controls
• in a rotarod test, mutant mice spend more time walking on top of the rotating rod after training than controls
• authors report that mice appear hyperactive, but the result is not statistically significant





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last database update
04/23/2024
MGI 6.23
The Jackson Laboratory