Phenotypes associated with this allele

• Allele Symbol: Brca2^tm1Arge
• Allele Name: targeted mutation 1, Argiris Efstratiadis
• Allele ID: MGI:1930615
• Summary: 6 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Brca2^tm1Arge/Brca2^tm1Arge	involves: 129S/SvEv * C57BL/6	MGI:2177212
ht2	Brca2^tm1Arge/Brca2^+	involves: 129S/SvEv * C57BL/6	MGI:2177215
ht3	Brca2^tm1Arge/Brca2^tm2Arge	involves: 129S/SvEv * C57BL/6	MGI:2177240
cn4	Brca2^tm1Arge/Brca2^tm2Arge Wap^tm1(cre)Arge/Wap^+	involves: 129S/SvEv * C57BL/6	MGI:2177237
cx5	Brca2^tm1Arge/Brca2^tm1Arge Trp53^tm1Tyj/Trp53^tm1Tyj	involves: 129S/SvEv * 129S2/SvPas * C57BL/6	MGI:2177218
cx6	Brca1^tm1Arge/Brca1^tm1Arge Brca2^tm1Arge/Brca2^tm1Arge	involves: 129S/SvEv * C57BL/6	MGI:2177216

Genotype
MGI:2177212

hm1

• Allelic Composition: Brca2^tm1Arge/Brca2^tm1Arge
• Genetic Background: involves: 129S/SvEv * C57BL/6

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

mortality/aging

embryonic lethality, complete penetrance ( J:40594 )

• lethality generally occurs prior to E8.5

embryo

abnormal embryo development ( J:40594 )

• at e5.5, mutant embryos appear similar to controls

• at e6.5, some mutant embryos appear similar to controls, while others exhibit short egg cylinders with expanded proamniotic cavities

decreased embryo size ( J:40594 )

• at E9.5, embryos exhibit a reduced size of the embryo region

• at E7.5, embryos are three layered egg cylinders, but show a reduced size of the embryonic region

• at E8.5, the embryos are smaller and lack somites, but development appears normal

abnormal extraembryonic tissue morphology ( J:40594 )

• at e7.5, embryos are surrounded by large giant cells and have a prominent ectoplacental cone and extraembryonic membrane

enlarged allantois ( J:40594 )

• at E9.5

abnormal amnion morphology ( J:40594 )

• at E8.5, the amnion development is not complete

abnormal proamniotic cavity morphology ( J:40594 )

• at e6.5, some mutant embryos appear similar to controls, while others exhibit short egg cylinders with expanded proamniotic cavities

• at E7.5, the amniotic folds are not fused and the proamniotic cavity remains open to the ectoplacental cavity

abnormal visceral yolk sac morphology ( J:40594 )

• expanded yolk sac at E9.5

growth/size/body

decreased embryo size ( J:40594 )

• at E7.5, embryos are three layered egg cylinders, but show a reduced size of the embryonic region

• at E8.5, the embryos are smaller and lack somites, but development appears normal

• at E9.5, embryos exhibit a reduced size of the embryo region

Genotype
MGI:2177215

ht2

• Allelic Composition: Brca2^tm1Arge/Brca2⁺
• Genetic Background: involves: 129S/SvEv * C57BL/6

neoplasm

neoplasm ( J:40594 )

N • while a single female developed a squamous cell carcinoma of the skin, the cause could not be attributed to the Brca2 mutation

N • no other heterozygous animals developed tumors

Genotype
MGI:2177240

ht3

• Allelic Composition: Brca2^tm1Arge/Brca2^tm2Arge
• Genetic Background: involves: 129S/SvEv * C57BL/6

normal phenotype

no abnormal phenotype detected ( J:70564 )

• mice are viable and fertile

Genotype
MGI:2177237

cn4

• Allelic Composition: Brca2^tm1Arge/Brca2^tm2Arge; Wap^tm1(cre)Arge/Wap⁺
• Genetic Background: involves: 129S/SvEv * C57BL/6

neoplasm

increased mammary adenocarcinoma incidence ( J:70564 )

• mammary tumors occur after long latency of at least 13 months of age

• T₅₀ for tumor-free survival is approximately 17 months of age

• at the end of the 20 month observation period, 20 of 26 animals developed mammary tumors; control animals developed none

• tumor pathology corresponded to two characteristic types, solid carcinoma and adenoacanthoma, with a mixture of the two types frequently appearing in the same tumor mass

endocrine/exocrine glands

increased mammary adenocarcinoma incidence ( J:70564 )

• mammary tumors occur after long latency of at least 13 months of age

• T₅₀ for tumor-free survival is approximately 17 months of age

• at the end of the 20 month observation period, 20 of 26 animals developed mammary tumors; control animals developed none

• tumor pathology corresponded to two characteristic types, solid carcinoma and adenoacanthoma, with a mixture of the two types frequently appearing in the same tumor mass

integument

increased mammary adenocarcinoma incidence ( J:70564 )

• mammary tumors occur after long latency of at least 13 months of age

• T₅₀ for tumor-free survival is approximately 17 months of age

• at the end of the 20 month observation period, 20 of 26 animals developed mammary tumors; control animals developed none

• tumor pathology corresponded to two characteristic types, solid carcinoma and adenoacanthoma, with a mixture of the two types frequently appearing in the same tumor mass

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
breast cancer		DOID:1612	OMIM:114480	J:70564

Genotype
MGI:2177218

cx5

• Allelic Composition: Brca2^tm1Arge/Brca2^tm1Arge; Trp53^tm1Tyj/Trp53^tm1Tyj
• Genetic Background: involves: 129S/SvEv * 129S2/SvPas * C57BL/6

mortality/aging

prenatal lethality ( J:40594 )

embryo

abnormal embryonic tissue morphology ( J:40594 )

• Trp53 deficiency appears to partially rescue the Brca2 homozygous phenotype in that some appear similar to wild-type and others are similar to or more advanced that the most advanced Brca2 single homozygous embryos

nervous system

exencephaly ( J:40594 )

Genotype
MGI:2177216

cx6

• Allelic Composition: Brca1^tm1Arge/Brca1^tm1Arge; Brca2^tm1Arge/Brca2^tm1Arge
• Genetic Background: involves: 129S/SvEv * C57BL/6

mortality/aging

embryonic lethality, complete penetrance ( J:40594 )

• embryonic lethal prior to E9.5

embryo

abnormal embryonic tissue morphology ( J:40594 )

• of two double homozygotes recovered at E9.5, one consisted of an allantois with a severely reduced embryonic region and the other consisted of a yolk sac and giant cells only