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Phenotypes Associated with This Genotype
Genotype
MGI:5439018
Allelic
Composition
Dicer1tm1Bdh/Dicer1tm1Bdh
Defb41tm1(icre)Psip/Defb41+
Genetic
Background
involves: 129S6/SvEvTac * C57BL/6N
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Defb41tm1(icre)Psip mutation (0 available); any Defb41 mutation (6 available)
Dicer1tm1Bdh mutation (4 available); any Dicer1 mutation (94 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
reproductive system
• sperm number is reduced in mutant epididymides; at 6 months, number of tubular cross sections without sperm is increased due to obstruction of efferent ducts; however, number of sperm with angulated tails is not increased at 2 months compared to controls
• disruption of epithelium resulting from fluid back-pressure is noted in 6-month old mice
• efferent ducts are enlarged at 2 months
• mutant males have a thicker smooth muscle layer than controls at 2 months, showing 3 muscle cell layers surrounding epididymal duct compared to one in controls
• initial segment (IS) of epididymis is much smaller than in controls and cannot be distinguished from the caput epididymis (CAP) whereas in controls the IS is readily discerned due to endogenous beta-gal activity
• epithelial cell layer is disorganized in mutants at 2 months with greater disturbance observed in 6-month old males
• numbers of apoptotic cells are higher in the IS and CAP of mutants relative to controls
• height of epithelium in initial segment of mutants is reduced below that of control animals; epithelial cell height in IS of mutants is significantly lower than in controls
• epithelial cells of IS in 45 day-old animals show regression to an undifferentiated state similar to that observed at 14 days
• despite increased cell proliferation, epididymides of mutants are significantly smaller than control (by weight at 2 months, but at 6 months there is no significant difference in epididymides weights)
• 2-3 month-old males fail to produce offspring when mated to wild-type females, even though sperm is detected in the cauda epididymides
• increased cell proliferation is observed in the proximal epididymides of 2 month-old mice based on Ki-67 staining (about 2-fold higher in the initial segment (IS) and 6-fold higher in the caput region (CAP) in mutants vs. control)

endocrine/exocrine glands
• disruption of epithelium resulting from fluid back-pressure is noted in 6-month old mice

cellular
• sperm number is reduced in mutant epididymides; at 6 months, number of tubular cross sections without sperm is increased due to obstruction of efferent ducts; however, number of sperm with angulated tails is not increased at 2 months compared to controls


Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
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last database update
03/19/2024
MGI 6.23
The Jackson Laboratory