Phenotypes associated with this allele

• Allele Symbol: Mir1a-2^tm1Dsr
• Allele Name: targeted mutation 1, Deepak Srivastava
• Allele ID: MGI:5575740
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Mir1a-2^tm1Dsr/Mir1a-2^tm1Dsr	involves: 129/Sv * C57BL/6	MGI:5575767
cx2	Mir1a-1^tm1Dsr/Mir1a-1^tm1Dsr Mir1a-2^tm1Dsr/Mir1a-2^tm1Dsr	involves: 129/Sv * 129P2/OlaHsd * C57BL/6	MGI:5575770

Genotype
MGI:5575767

hm1

• Allelic Composition: Mir1a-2^tm1Dsr/Mir1a-2^tm1Dsr
• Genetic Background: involves: 129/Sv * C57BL/6

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

mortality/aging

abnormal survival ( J:211548 )

• occasional sudden death in adult mice

lethality during fetal growth through weaning, incomplete penetrance ( J:211548 )

• 50% lethality by weaning

• most deaths occur from E15.5 to shortly after birth

cardiovascular system

abnormal heart morphology ( J:211548 )

abnormal myocardium layer morphology ( J:211548 )

• 20% increase in the number of cardiomyocytes

• extended period of cell division

ventricular septal defect ( J:211548 )

• large septal defects in about 50% of embryos leads to death within a few hours of birth

enlarged heart ( J:211548 )

• embryonic hearts occasionally are somewhat enlarged but superficially appear normal otherwise

increased heart weight ( J:211548 )

• increased heart to body weight ratio at 4 to 6 months of age

thick ventricular wall ( J:211548 )

• determined by echocardiography

pericardial edema ( J:211548 )

• sometimes, before birth

dilated heart ( J:211548 )

• develops rapidly in about 15% of surviving mice

abnormal cardiovascular system physiology ( J:211548 )

• appears by 2-3 months of age in about 15% of survivors

decreased heart rate ( J:211548 )

• significantly reduced heart rate

abnormal heart electrocardiography waveform feature ( J:211548 )

• shortened delay between atrial and ventricular depolarizations

prolonged QRS complex duration ( J:211548 )

homeostasis/metabolism

pericardial edema ( J:211548 )

• sometimes, before birth

abnormal atrial thrombosis ( J:211548 )

• atrial thrombi found in about 15% of survivors by 2-3 months of age

• atrial thrombi lead to death

muscle

abnormal myocardium layer morphology ( J:211548 )

• 20% increase in the number of cardiomyocytes

• extended period of cell division

growth/size/body

enlarged heart ( J:211548 )

• embryonic hearts occasionally are somewhat enlarged but superficially appear normal otherwise

increased heart weight ( J:211548 )

• increased heart to body weight ratio at 4 to 6 months of age

Genotype
MGI:5575770

cx2

• Allelic Composition: Mir1a-1^tm1Dsr/Mir1a-1^tm1Dsr; Mir1a-2^tm1Dsr/Mir1a-2^tm1Dsr
• Genetic Background: involves: 129/Sv * 129P2/OlaHsd * C57BL/6

mortality/aging

postnatal lethality, complete penetrance ( J:207845 )

• fail to survive to weaning

• no survival past 10 days of age

neonatal lethality, incomplete penetrance ( J:207845 )

• about 25% of mice die soon after birth although birth weight is normal

cardiovascular system

abnormal heart morphology ( J:207845 )

overriding aortic valve ( J:207845 )

• in some mice

increased heart atrium size ( J:207845 )

abnormal heart ventricle morphology ( J:207845 )

ventricular septal defect ( J:207845 )

• in some mice

abnormal heart right ventricle size ( J:207845 )

• expansion of the superior portion of the right ventricle

dilated heart ( J:207845 )

• extensive dilation of all heart chambers starting at 4 days of age, particularly the right atrium

abnormal cardiovascular system physiology ( J:207845 )

decreased cardiac muscle contractility ( J:207845 )

• impaired fractional shortening by 2 days of age

abnormal heart echocardiography feature ( J:207845 )

• poor systolic function

• frequent ventricular thrombi by 4 days of age

abnormal sinus arrhythmia ( J:207845 )

• frequent sinus pauses

abnormal heart electrocardiography waveform feature ( J:207845 )

prolonged PR interval ( J:207845 )

prolonged QRS complex duration ( J:207845 )

prolonged QT interval ( J:207845 )

muscle

decreased cardiac muscle contractility ( J:207845 )

• impaired fractional shortening by 2 days of age

abnormal sarcomere morphology ( J:207845 )

• significant sarcomere disruptions at birth in ventricular cardiomyocytes

• only 10% of mice with well ordered sarcomeres in cardiomyocytes