Phenotypes associated with this allele

• Allele Symbol: Smarcd3^tm1.2Bbr
• Allele Name: targeted mutation 1.2, Benoit G Bruneau
• Allele ID: MGI:6368007
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Smarcd3^tm1.2Bbr/Smarcd3^tm1.2Bbr	B6.129(Cg)-Smarcd3^tm1.2Bbr	MGI:6368030
hm2	Smarcd3^tm1.2Bbr/Smarcd3^tm1.2Bbr	either: (involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * SJL) or (involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * ICR * SJL)	MGI:6368028

Genotype
MGI:6368030

hm1

• Allelic Composition: Smarcd3^tm1.2Bbr/Smarcd3^tm1.2Bbr
• Genetic Background: B6.129(Cg)-Smarcd3^tm1.2Bbr

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

mortality/aging

embryonic lethality during organogenesis, complete penetrance ( J:257963 )

• Background Sensitivity: survival only until E12.5-13.5 when backcrossed into C57BL/6 for 10 generations compared to E14.5 on a mixed background

cardiovascular system

abnormal myocardial trabeculae morphology ( J:257963 )

• E11.5 hearts have fewer or less well-developed trabeculae

thin myocardium compact layer ( J:257963 )

• E11.5 hearts exhibit a thin compact layer

abnormal heart development ( J:257963 )

• E11.5 hearts exhibit reduced atrial septum growth, impaired atrioventricular cushion formation, and fewer or less well-developed trabeculae

abnormal atrioventricular cushion morphology ( J:257963 )

• E11.5 hearts exhibit impaired atrioventricular cushion formation

abnormal interatrial septum morphology ( J:257963 )

• E11.5 hearts exhibit reduced atrial septum growth

muscle

abnormal myocardial trabeculae morphology ( J:257963 )

• E11.5 hearts have fewer or less well-developed trabeculae

thin myocardium compact layer ( J:257963 )

• E11.5 hearts exhibit a thin compact layer

Genotype
MGI:6368028

hm2

• Allelic Composition: Smarcd3^tm1.2Bbr/Smarcd3^tm1.2Bbr
• Genetic Background: either: (involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * SJL) or (involves: 129S1/Sv * 129X1/SvJ * C57BL/6 * ICR * SJL)

mortality/aging

lethality throughout fetal growth and development, complete penetrance ( J:257963 )

• most mutants are dead at E14.5, with a few surviving past E14.5

• Background Sensitivity: mutants on the mixed background live a little longer (E14.5) compared to mice on a congenic C57BL/6 background which live to E12.5-E13.5

• however, mutants are recovered alive and with normal morphology until E12.5-E14.5

cardiovascular system

abnormal interventricular septum morphology ( J:257963 )

• E12.5 hearts exhibit underdeveloped interventricular septa

ventricular septal defect ( J:257963 )

• the few surviving E14.5 mutants exhibit disorganized interventricular septum leading to ventricular septal defects

thin ventricular wall ( J:257963 )

• ventricular free walls are much thinner than in wild-type in the few surviving E14.5 mutants

dilated heart ( J:257963 )

• E12.5 hearts exhibit dilated inner chambers

hemorrhage ( J:257963 )

• broad regions of hemorrhage at E14.5

decreased heart left ventricle muscle contractility ( J:257963 )

• left ventricle fractional shortening is reduced in E13.5 hearts

• inter-ventricular septal fractional thickening is lower at E13.5, indicating reduced myocardial contraction

abnormal cardiac muscle relaxation ( J:257963 )

• the E:A ratios of hearts for both the left and right ventricles is increased, possibly indicating impaired cardiac relaxation

decreased fetal cardiomyocyte proliferation ( J:257963 )

• cardiomyocyte proliferation is decreased in E12.5 ventricles

abnormal heart echocardiography feature ( J:257963 )

• E13.5 hearts show reduced left ventricle fractional shortening, inter-ventricular septal fractional thickening, and increased E:A ratio for both the left and right ventricles

• however, no regurgitation between atria and ventricles is seen

muscle

decreased heart left ventricle muscle contractility ( J:257963 )

• left ventricle fractional shortening is reduced in E13.5 hearts

• inter-ventricular septal fractional thickening is lower at E13.5, indicating reduced myocardial contraction

abnormal cardiac muscle relaxation ( J:257963 )

• the E:A ratios of hearts for both the left and right ventricles is increased, possibly indicating impaired cardiac relaxation

decreased fetal cardiomyocyte proliferation ( J:257963 )

• cardiomyocyte proliferation is decreased in E12.5 ventricles

abnormal sarcomere morphology ( J:257963 )

• sarcomeres of hearts are disarrayed at E12.5 and the thick and thin filaments are discontinuous and poorly aligned

abnormal M line morphology ( J:257963 )

• the M bands are almost undetectable in cardiomyocytes

abnormal I band morphology ( J:257963 )

• the I bands are almost undetectable in cardiomyocytes

abnormal Z line morphology ( J:257963 )

• cardiac Z-disks are loosely packed and do not have defined borders

• localization of desmin in Z-disks of cardiomyocytes is disturbed

cellular

decreased fetal cardiomyocyte proliferation ( J:257963 )

• cardiomyocyte proliferation is decreased in E12.5 ventricles