Phenotypes Associated with This Genotype

Genotype
MGI:5575770

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

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

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