Phenotypes Associated with This Genotype

Genotype
MGI:5908988

• Allelic Composition: Tg(Myh6-Tnnt2*R92W)1Jcf/0
• Genetic Background: B6.Cg-Tg(Myh6-Tnnt2*R92W)1Jcf

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

cardiovascular system

abnormal heart morphology ( J:104369 )

• adult hearts show myocyte disarray and degeneration, mild inflammatory cell infiltration, occasional hypertrophied cells, and minimal fibrosis

abnormal myocardial fiber morphology ( J:104369 )

• isolated myofilament lysis and discontinuity in adult ventricular myocytes

decreased myocardial fiber size ( J:104369 )

• decrease in myocyte size that results in a decrease in ventricular mass

myocardial fiber degeneration ( J:104369 )

• adult hearts show myocyte degeneration

small heart ( J:104369 )

• hearts are smaller

decreased heart weight ( J:104369 )

• heart weigh/body weight ratio is smaller

abnormal heart left ventricle morphology ( J:104369 )

• ventricular mass is decreased by 14% in 6 month old mice

• 6 month old mice exhibit mild degrees of myofibrillar lysis and prominent atrial natriuretic factor granules in left ventricular tissue

• however, no sarcomere loss or destruction, mitochondrial abnormalities, or apoptotic nuclei are seen in left ventricular tissue

decreased cardiac muscle contractility ( J:104369 )

• hearts exhibit impaired systolic performance at baseline and with inotropic challenge

decreased cardiac muscle relaxation ( J:104369 )

• diastolic function, as indicated by increases in end-diastolic pressure and decreases in the rate of relaxation, is impaired, with hearts unable to increase their rate of relaxation in response to increased perfusate of calcium

decreased left ventricle developed pressure ( J:104369 )

• hearts are less able to increase developed pressure upon inotropic challenge

decreased left ventricle systolic pressure ( J:104369 )

• left ventricular systolic pressure and the rate of pressure development (+dP/dt) are lower in response to increasing calcium concentrations

cardiomyopathy ( J:104369 )

• hearts exhibit a more severe cardiomyopathy than Tg(Myh6-Tnnt2*R92L)1Jcf /0 mice

• maker analysis shows early activation of the fetal gene or hypertrophic gene program indicating early disease onset, however, overt ventricular hypertrophy is not seen

muscle

abnormal myocardial fiber morphology ( J:104369 )

• isolated myofilament lysis and discontinuity in adult ventricular myocytes

decreased myocardial fiber size ( J:104369 )

• decrease in myocyte size that results in a decrease in ventricular mass

myocardial fiber degeneration ( J:104369 )

• adult hearts show myocyte degeneration

decreased cardiac muscle contractility ( J:104369 )

• hearts exhibit impaired systolic performance at baseline and with inotropic challenge

decreased cardiac muscle relaxation ( J:104369 )

• diastolic function, as indicated by increases in end-diastolic pressure and decreases in the rate of relaxation, is impaired, with hearts unable to increase their rate of relaxation in response to increased perfusate of calcium

cardiomyopathy ( J:104369 )

• hearts exhibit a more severe cardiomyopathy than Tg(Myh6-Tnnt2*R92L)1Jcf /0 mice

• maker analysis shows early activation of the fetal gene or hypertrophic gene program indicating early disease onset, however, overt ventricular hypertrophy is not seen

dilated sarcoplasmic reticulum ( J:104369 )

• adult ventricular myocytes exhibit dilated sarcomeric reticulum

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
hypertrophic cardiomyopathy 2		DOID:0110308	OMIM:115195	J:104369