Phenotypes Associated with This Genotype

Genotype
MGI:3722144

• Allelic Composition: pma/pma
• Genetic Background: involves: CF-1

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

limbs/digits/tail

clubfoot ( J:6590 , J:8195 , J:86652 )

• bilateral club foot deformity at birth with no clinical progression (J:8195)

muscle

abnormal muscle fiber morphology ( J:4723 , J:4724 , J:8195 )

• chronic paralysis with tetrodotoxin causes no further depression of primary myotube numbers but secondary myotube numbers are reduced by 40% (J:4724)

• muscle fibers in the tibialis anterior and extensor digitorum longus (EDL) muscles at 30 days of age are smaller in bulk and have fewer numbers of muscle fibers, all of which are of smaller caliber (J:8195)

• myofibrils are poorly organized, especially in the small-caliber fibers (J:8195)

• EDL muscles have a greater number of primary myotubes than controls at E12-13 but by E15, almost half of them degenerate (J:8195)

• in newborns, the number of secondary myotubes in EDL muscles is 60% of control numbers and by 4 weeks of age, massive muscle atrophy and degeneration sets in (J:8195)

• muscle fibers are less tightly packed, resulting in ovoid rather than polygonal cells (J:8195)

muscle degeneration ( J:4723 )

• exhibit postnatal degeneration of muscle which results in the adult phenotype of a few very attenuated fibers interspersed with large amounts of fat and connective tissue

muscular atrophy ( J:4723 , J:4724 , J:6590 , J:8195 , J:86652 )

• neurogenic muscular atrophy in the peroneal muscle group (J:8195)

• muscles in the anterolateral hind legs, including tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fourth and fifth tibial muscles are atrophic and reduced to fibrous strings (J:8195)

myopathy ( J:8195 )

nervous system

abnormal nervous system morphology ( J:4723 , J:4724 , J:6590 , J:8195 , J:86652 )

• the peroneal and saphenous nerves are entirely absent (J:4723)

• however, the sciatic, tibial, sural, and other peripheral nerves appear normal (J:8195)

abnormal innervation pattern to muscle ( J:4723 , J:4724 , J:8195 )

• primary myotubes develop in aneural muscles but require innervation for postnatal maintenance, while secondary myotube development is not dependent upon innervation (J:4723)

• lack innervation to the peroneal muscle group due to absence of the common peroneal nerve branch (J:8195)

behavior/neurological

abnormal gait ( J:6590 , J:86652 )

• unusual gait due to the dropped foot (J:6590)

skeleton

abnormal joint mobility ( J:4724 )

• ankle joint is immobile by the time of birth

growth/size/body

postnatal growth retardation ( J:6590 )

• growth is slightly delayed

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
clubfoot		DOID:11836	OMIM:119800	J:8195
neurogenic-type arthrogryposis multiplex congenita-2		DOID:0090124	OMIM:208100	J:8195