About   Help   FAQ
Phenotypes Associated with This Genotype
Genotype
MGI:5906349
Allelic
Composition
Dicer1tm1Smr/Dicer1tm1Smr
Tg(Myh6-cre)2182Mds/0
Genetic
Background
involves: 129S7/SvEvBrd * FVB/N
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Dicer1tm1Smr mutation (1 available); any Dicer1 mutation (61 available)
Tg(Myh6-cre)2182Mds mutation (3 available)
phenotype observed in females
phenotype observed in males
N normal phenotype

Dilated cardiomyopathy in Dicer1tm1Smr/Dicer1tm1Smr Tg(Myh6-cre)2182Mds/0 hearts

mortality/aging
• all mice die within 4 days after birth

behavior/neurological
• pups become fragile and exhibit decreased spontaneous activity preceding death

cardiovascular system
• integrity of cardiomyocytes is impaired
• neonatal cardiomyocytes show disarrayed myofibrils
• decrease in fractional shortening and an increase in the left ventricle posterior wall thickness at end diastole without change at end systole, indicating a loss of ventricle force generation
• hearts exhibit dysregulation of cardiac contractile protein expression
• however, sarcoplasmic reticulum calcium uptake rates are normal in hearts
• echocardiography indicates severe left ventricle dilation with a decrease in fractional shortening and an increase in the left ventricle posterior wall thickness at end diastole without change at end systole, indicating a loss of ventricle force generation
• hearts only beat about half of the rate
• increase in apoptosis in the left atrium of P2 hearts and in restricted areas of the ventricular apex and left ventricle wall, however no increase in apoptosis is seen before P0
• however, cardiomyocyte proliferation, cell size, and cell number are normal

cellular
• increase in apoptosis in the left atrium of P2 hearts and in restricted areas of the ventricular apex and left ventricle wall, however no increase in apoptosis is seen before P0
• however, cardiomyocyte proliferation, cell size, and cell number are normal

homeostasis/metabolism
• accumulation of blood clots and/or thrombin in the left atrium
• accumulation of blood clots and/or thrombin in the left ventricle and left atrium

muscle
• integrity of cardiomyocytes is impaired
• decrease in fractional shortening and an increase in the left ventricle posterior wall thickness at end diastole without change at end systole, indicating a loss of ventricle force generation
• hearts exhibit dysregulation of cardiac contractile protein expression
• however, sarcoplasmic reticulum calcium uptake rates are normal in hearts
• increase in apoptosis in the left atrium of P2 hearts and in restricted areas of the ventricular apex and left ventricle wall, however no increase in apoptosis is seen before P0
• however, cardiomyocyte proliferation, cell size, and cell number are normal
• less sarcomeres in heart ventricles and the sarcomeres that are present are disarrayed and shorter
• however, intercalated discs appear normal

Mouse Models of Human Disease
DO ID OMIM ID(s) Ref(s)
dilated cardiomyopathy DOID:12930 OMIM:PS115200
J:131962


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)
Citing These Resources
Funding Information
Warranty Disclaimer & Copyright Notice
Send questions and comments to User Support.
last database update
09/10/2019
MGI 6.14
The Jackson Laboratory