Phenotypes Associated with This Genotype

Genotype
MGI:2176876

• Allelic Composition: Dmd^mdx/Dmd^mdx; Utrn^tm1Jrs/Utrn^tm1Jrs
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/10ScSn

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

mortality/aging

premature death ( J:42389 , J:59675 )

♀ • die between 4 and 14 weeks of age, with only half surviving beyond 8 weeks (J:42389)

♀ • lifespan is 4-20 weeks (J:59675)

growth/size/body

decreased body size ( J:42389 )

♀ • significantly smaller by 4 weeks of age

postnatal growth retardation ( J:42389 , J:59675 )

♀ • grow more slowly after 3 weeks of age (J:42389)

♀ (J:59675)

muscle

myocardium necrosis ( J:42389 )

♀ • large areas of necrotic myocytes with infiltrating mononuclear cells are present in 5 of 9 mutant hearts examined at 8 to 11 weeks of age

♀ • necrosis is most prominent in the epicardial surface of the right ventricle, but is seen throughout both ventricles, however ventricles are not dilated or hypertrophic

skeletal muscle interstitial fibrosis ( J:42389 )

♀ • seen by 10 weeks of age

skeletal muscle necrosis ( J:42389 )

♀ • necrosis begins earlier and persists longer than in single Dmd mutants and leads to fibrosis

dystrophic muscle ( J:42389 , J:59675 )

♀ • begin to exhibit symptoms of skeletal muscle disease at 4 weeks of age and severity progresses with age (J:42389)

♀ • develop severe skeletal muscle dystrophy (J:59675)

muscle degeneration ( J:42389 )

♀ • muscle degeneration begins earlier than in single Dmd mutants

abnormal muscle physiology ( J:42389 )

♀

cardiomyopathy ( J:42389 , J:59675 )

♀ (J:42389)

♀ • develop moderate to severe cardiomyopathy (J:59675)

abnormal muscle relaxation ( J:42389 )

♀ • relaxation time of muscle (time from peak force to baseline) is greatly prolonged

muscle weakness ( J:42389 )

♀ • sternomastoid muscle generates only 40-60% as much tension as controls in response to stimulation of its nerve, indicating weakness

cardiovascular system

myocardium necrosis ( J:42389 )

♀ • large areas of necrotic myocytes with infiltrating mononuclear cells are present in 5 of 9 mutant hearts examined at 8 to 11 weeks of age

♀ • necrosis is most prominent in the epicardial surface of the right ventricle, but is seen throughout both ventricles, however ventricles are not dilated or hypertrophic

cardiomyopathy ( J:42389 , J:59675 )

♀ (J:42389)

♀ • develop moderate to severe cardiomyopathy (J:59675)

nervous system

abnormal neuromuscular synapse morphology ( J:42389 , J:60776 )

♀ • exhibit fewer junctional folds in the neuromuscular junction (J:42389)

♀ • distribution of acetylcholine receptors within the synapse branches is abnormal, with a patchy distribution (J:60776)

limbs/digits/tail

abnormal limb morphology ( J:42389 , J:59675 )

♀ • exhibit contracted and stiff limbs at 4 weeks of age (J:42389)

♀ • severe limb contractures (J:59675)

skeleton

kyphosis ( J:42389 , J:59675 )

♀ (J:42389)

♀ (J:59675)

behavior/neurological

abnormal gait ( J:42389 )

♀ • abnormal waddling gait is seen at 4 weeks of age

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Duchenne muscular dystrophy		DOID:11723	OMIM:310200	J:42389 , J:59675