Phenotypes Associated with This Genotype

Genotype
MGI:3813458

• Allelic Composition: Tg(DMPK/tetO-EGFP/DMPK)5-313Masm/0
• Genetic Background: involves: FVB/N

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

muscle

skeletal muscle fiber atrophy ( J:207560 )

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit muscle fiber atrophy

increased variability of skeletal muscle fiber size ( J:207560 )

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit muscles with a greater degree of fiber size variability

centrally nucleated skeletal muscle fibers ( J:207560 )

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit muscles with an increase in centrally nucleated fibers

dystrophic muscle ( J:207560 )

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit an increase in myotonic dystrophy disease severity compared to mice treated with doxycycline starting at 2 months of age for a total of 8 weeks, showing a PR interval increase of 46.75% compared to 17.93% in the adult-induced mice, worse myotonia score, and more severe loss of grip strength, although a slightly milder muscle histology

impaired muscle relaxation ( J:131302 , J:207560 )

• following treatment with doxycycline, mice exhibit myotonia (J:131302)

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit weak and intermittent myotonia at 2 weeks of age that increases in severity by 4 weeks of age (J:207560)

cardiovascular system

abnormal atrioventricular node conduction ( J:131302 )

• following treatment with doxycycline, mice develop progressive heart block

prolonged PR interval ( J:131302 , J:207560 )

• following treatment with doxycycline (J:131302)

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth exhibit a lengthened PR interval by 4 and 6 weeks of age, indicating cardiac conduction defects (J:207560)

behavior/neurological

decreased grip strength ( J:207560 )

• mice treated with doxycycline throughout gestation, birth, and rearing up to 6 weeks after birth have weaker forelimb grip strength at 4 and 6 weeks of age

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
myotonic dystrophy type 1		DOID:11722	OMIM:160900	J:207560