ApcLocation:
Chr18:34380638-34479735 bp, + strand
Genetic Position: Chr18,
15.0 cM
Mutation origin
Strain of Origin:
C57BL/6J
Mutation description
Allele
Type:
Chemically induced (ENU)
Mutation:
Single point mutation
A transversion point mutation that alters nucleotide 2549 from a T to an A. This converts codon 850 from one encoding a leucine to a stop codon. (J:830)
Inheritance:
Dominant
Find Mice (IMSR)
Mouse strains and cell lines available from the
International Mouse Strain Resource
(IMSR)
body weight of mice at time of sacrifice differs significantly from Brca2-heterozygous and wild-type animals; mice show lower weight gain from start to end of experiment compared to other experimental genotypes
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
no differences are observed in branching of female mammary glands among genotypes or wild-type females
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
by 65 days after ENU treatment, 100% of females develop mammary tumors with a multiplicity of 6.7 +/- 2.8
males develop tumors at a very low incidence and with a tumor multiplicity of 0.4 +/- 0.5, 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
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
no differences are observed in branching of female mammary glands among genotypes or wild-type females
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
the number and size of microadenomas in the intestine are decreased compared to in ApcMin heterozygotes due to an increased in Caspase-3 dependent apoptosis
mice fail to develop colon tumors unlike ApcMin heterozygotes