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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID
Brca1tm1Bhk
targeted mutation 1, Beverly H Koller
MGI:1857931
Summary 6 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
Brca1tm1Bhk/Brca1tm1Bhk involves: 129P2/OlaHsd * BALB/c * C57BL/6 MGI:3814403
hm2
Brca1tm1Bhk/Brca1tm1Bhk involves: 129P2/OlaHsd * C57BL/6 * DBA/2 MGI:2174676
ht3
Brca1tm1Bhk/Brca1+ C.129P2-Brca1tm1Bhk MGI:5517368
ht4
Brca1tm1Bhk/Brca1+ involves: 129P2/OlaHsd * C57BL/6 * DBA/2 MGI:2174677
cx5
Brca1tm1Bhk/Brca1tm1Bhk
Cdkn2ctm1Yxi/Cdkn2ctm1Yxi
C.129-Cdkn2ctm1Yxi Brca1tm1Bhk MGI:5517367
cx6
Brca1tm1Bhk/Brca1+
Cdkn2ctm1Yxi/Cdkn2ctm1Yxi
C.129-Cdkn2ctm1Yxi Brca1tm1Bhk MGI:5517370


Genotype
MGI:3814403
hm1
Allelic
Composition
Brca1tm1Bhk/Brca1tm1Bhk
Genetic
Background
involves: 129P2/OlaHsd * BALB/c * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• lethality occurs around E10.5; survival is not altered with incorporation of BALB/c genetic background

nervous system
• embryos characteristically exhibit an open cranial neural tube at E8-E8.5

embryo
• embryos characteristically exhibit an open cranial neural tube at E8-E8.5




Genotype
MGI:2174676
hm2
Allelic
Composition
Brca1tm1Bhk/Brca1tm1Bhk
Genetic
Background
involves: 129P2/OlaHsd * C57BL/6 * DBA/2
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging

embryo
• embryos appear underdeveloped by E8.5 and are clearly smaller at E9.5
• abnormal contours in the neuroepithelium are seen
• excessive cell death is noted in selected cell populations, especially in the hindbrain
• fail to close the neural tube completely
• variable degrees of severity are observed

nervous system
• abnormal contours in the neuroepithelium are seen
• excessive cell death is noted in selected cell populations, especially in the hindbrain
• fail to close the neural tube completely
• variable degrees of severity are observed
• variable degrees of severity are observed

growth/size/body
• embryos appear underdeveloped by E8.5 and are clearly smaller at E9.5




Genotype
MGI:5517368
ht3
Allelic
Composition
Brca1tm1Bhk/Brca1+
Genetic
Background
C.129P2-Brca1tm1Bhk
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
cellular
• cellular proliferation is inhibited in young and old mammary epithelial cells

endocrine/exocrine glands
• cellular proliferation is inhibited in young and old mammary epithelial cells
• less than 10% of mutants develop mammary tumors

growth/size/body
• decrease in body weight from 12 to 24 weeks of age

integument
• cellular proliferation is inhibited in young and old mammary epithelial cells
• less than 10% of mutants develop mammary tumors

neoplasm
• less than 10% of mutants develop mammary tumors




Genotype
MGI:2174677
ht4
Allelic
Composition
Brca1tm1Bhk/Brca1+
Genetic
Background
involves: 129P2/OlaHsd * C57BL/6 * DBA/2
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
normal phenotype
• no aberrant phenotype is seen up to 5 months of age




Genotype
MGI:5517367
cx5
Allelic
Composition
Brca1tm1Bhk/Brca1tm1Bhk
Cdkn2ctm1Yxi/Cdkn2ctm1Yxi
Genetic
Background
C.129-Cdkn2ctm1Yxi Brca1tm1Bhk
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
Cdkn2ctm1Yxi mutation (1 available); any Cdkn2c mutation (16 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• no viable embryos are identified beyond E14.5




Genotype
MGI:5517370
cx6
Allelic
Composition
Brca1tm1Bhk/Brca1+
Cdkn2ctm1Yxi/Cdkn2ctm1Yxi
Genetic
Background
C.129-Cdkn2ctm1Yxi Brca1tm1Bhk
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Brca1tm1Bhk mutation (0 available); any Brca1 mutation (113 available)
Cdkn2ctm1Yxi mutation (1 available); any Cdkn2c mutation (16 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
endocrine/exocrine glands
• mammary glands of virgin females show a decrease in the expansion of luminal progenitors seen in single Cdkn2c homozygotes to normal levels but show an increase in the expansion of basal/myoepithelial cells
• 38% of mutants develop breast cancer before 1 year of age and 87% by 22 months of age
• mammary tumors show high degree of heterogeneity, increased population of CK5+ cells, loss of wild-type allele of Brca1 in CK5+ tumor cells, ERalpha negativity and invasiveness and metastasis
• mammary tumors are transformed from a luminal subtype that is seen in single Cdkn2c homozygotes into a basal-like subtype
• poorly differentiated carcinoma with squamous metaplasia

integument
• mammary glands of virgin females show a decrease in the expansion of luminal progenitors seen in single Cdkn2c homozygotes to normal levels but show an increase in the expansion of basal/myoepithelial cells
• 38% of mutants develop breast cancer before 1 year of age and 87% by 22 months of age
• mammary tumors show high degree of heterogeneity, increased population of CK5+ cells, loss of wild-type allele of Brca1 in CK5+ tumor cells, ERalpha negativity and invasiveness and metastasis
• mammary tumors are transformed from a luminal subtype that is seen in single Cdkn2c homozygotes into a basal-like subtype
• poorly differentiated carcinoma with squamous metaplasia

neoplasm
• 38% of mutants develop breast cancer before 1 year of age and 87% by 22 months of age
• mammary tumors show high degree of heterogeneity, increased population of CK5+ cells, loss of wild-type allele of Brca1 in CK5+ tumor cells, ERalpha negativity and invasiveness and metastasis
• mammary tumors are transformed from a luminal subtype that is seen in single Cdkn2c homozygotes into a basal-like subtype
• poorly differentiated carcinoma with squamous metaplasia
• 4 of 13 (31%) mammary tumors metastasize to the lung and blood vessels after 1 year of age

Mouse Models of Human Disease
DO ID OMIM ID(s) Ref(s)
breast cancer DOID:1612 OMIM:114480
J:198018





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