Phenotypes associated with this allele

• Allele Symbol: Clcn1^adr-mto
• Allele Name: myotonia
• Allele ID: MGI:1855953
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Clcn1^adr-mto/Clcn1^adr-mto	SWR/J-Clcn1^adr-mto/J	MGI:3581032

Genotype
MGI:3581032

hm1

• Allelic Composition: Clcn1^adr-mto/Clcn1^adr-mto
• Genetic Background: SWR/J-Clcn1^adr-mto/J

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

behavior/neurological

abnormal righting response ( J:14251 )

• mice exhibit an arrested development of righting response

abnormal voluntary movement ( J:6814 , J:14251 )

• at 2 weeks of age, mice exhibit stiff extensor postures of the limbs when gently dropped from a height of about 10 cm (J:6814)

• when tested after 2 hours at 5 degrees Celsius, extensor posture is elicited more easily and its duration is increased by 50% (J:6814)

• unlike in wild-type mice, scratching motion with hindlimb is not rapid (J:6814)

• when place in an ice water bath mice exhibit a stiff extensor posture of the hindlimbs that is most prominent in the first minute and gradually subsides (J:6814)

• mice exhibit stiffening of hindlimbs when supine with difficulty righting and stiffening of hindlimbs after rapid movement (J:14251)

• abnormal phenotype is visible at 2 weeks of age and is progressive (J:14251)

impaired limb coordination ( J:6814 )

• mice are capable of swimming but alternate movements of the hindlimbs are not well coordinated

abnormal gait ( J:6814 )

• mice exhibit a slightly stiff gait and walk slower than wild-type mice

growth/size/body

decreased body weight ( J:6814 )

• at 30 days mice weigh 10% less than wild-type mice and this difference increases to 40% in adulthood

muscle

muscle phenotype ( J:6814 )

N • mice do not display muscle fiber necrosis, grouped atrophy or inflammatory infiltrates

increased skeletal muscle mass ( J:6814 )

• by day 70, mice exhibit increased muscle bulk in the neck and shoulder girdle muscles compared to wild-type mice

abnormal muscle physiology ( J:6814 )

• percussion of muscles occasionally produces a sustained local contraction with sustained posturing

• however, muscle weakness is not observed

abnormal muscle electrophysiology ( J:6814 , J:14251 )

• unlike in wild-type mice, myotonic discharges are detected from anesthetized mice whose muscles are percussed or stretched (J:6814)

• unlike in wild-type mice, myotonic discharges continue for several minutes after amputation (J:6814)

• mice exhibit myotonic discharges in limbs, abdominal, tongue, and eye muscles (J:14251)

impaired muscle relaxation ( J:14251 )

• mice exhibit myotonia

nervous system

axon degeneration ( J:6814 )

• by 225 days, mice exhibit degeneration of myelinated axons in the ventrolateral funiculus at all levels of the spinal cord

• however, nerve roots and mixed peripheral nerves are not affected

reproductive system

reduced fertility ( J:6814 )

• mice are not reliable breeders

skeleton

kyphosis ( J:6814 )

• Background Sensitivity: mice usually develop mild dorsal kyphosis on a mixed background

• at day 80, mice exhibit thoracic kyphosis at the T3 to T5 level

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
myotonia congenita		DOID:2106		J:16954