Mouse Genome Informatics
cx
    ApcMin/Apc+
Brca2tm1Mbn/Brca2+

B6.Cg-Brca2tm1Mbn ApcMin
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
       
growth/size/body
N
• body weight of mice at time of sacrifice does not differ significantly from Apc-heterozygous, Brca2-heterozygous, or wild-type animals (J:67445)

reproductive system
N
• only observed in 1/8 ENU-treated males, similar to wild-type males (1/9) (J:67445)
• absent in 22% of ENU-treated females (J:67445)
• remaining follicles are degenerating in ENU-treated females (J:67445)
• arrested follicular development is 6-fold more prevalent compared to ENU-treated Brca2-deficient mice (J:67445)
• complete loss of follicles (ovarian atrophy) is observed in about 25% of ENU-treated mutants, whereas almost no incidence is observed in ENU-treated wild-type or Brca2-mutant females (J:67445)
• observed in ENU-treated females displaying ovarian failure (atrophy); endometrium and myometrium appear immature (J:67445)
• reduced in thickness and lined with vacuolated cells indicative of anestrus in ENU-treated females (J:67445)

tumorigenesis
• multiple intestinal tumors are observed in ENU-treated mice
• by 65 days after ENU treatment, 100% of females develop mammary tumors with a multiplicity of 7.2 +/- 2.7, whereas only 7% of wild-type females develop tumors
• males develop tumors at a very low incidence and with a tumor multiplicity of 0.2 +/- 0.3, whereas no wild-type or Brca2-heterozygous males developed mammary tumors
• tumors in male and female mice are adenoacanthomas, characterized by undifferentiated acini and tubules with centrally confined squamous cells and keratin; most tumors contain proportions of adenomatous and squamous cell types
• tumors with predominantly squamous differentiation, moderate to marked inflammation in and around tumors is observed, with areas of fibrosis; in some cases, squamous component becomes cystic and is filled with keratinous debris
• invasion or metastases into the mammary lymph nodes was not observed during time course of study

endocrine/exocrine glands
• in ENU treated mice, male mammary ducts are elongated and in most males have extended to the lymph node of the fourth mammary gland, whereas wild-type and Brca2-heterozygous males are born with a small mammary gland rudiment, which grows no further, and no nipple (J:67445)
• no differences are observed in branching of female mammary glands among genotypes or wild-type females (J:67445)
(J:67445)
• absent in 22% of ENU-treated females (J:67445)
• remaining follicles are degenerating in ENU-treated females (J:67445)
• arrested follicular development is 6-fold more prevalent compared to ENU-treated Brca2-deficient mice (J:67445)
• complete loss of follicles (ovarian atrophy) is observed in about 25% of ENU-treated mutants, whereas almost no incidence is observed in ENU-treated wild-type or Brca2-mutant females (J:67445)

homeostasis/metabolism

integument
• in ENU treated mice, male mammary ducts are elongated and in most males have extended to the lymph node of the fourth mammary gland, whereas wild-type and Brca2-heterozygous males are born with a small mammary gland rudiment, which grows no further, and no nipple (J:67445)
• no differences are observed in branching of female mammary glands among genotypes or wild-type females (J:67445)
(J:67445)

Mouse Models of Human Disease
OMIM IDRef(s)
Breast Cancer 114480 J:67445