Phenotypes Associated with This Genotype

Genotype
MGI:3783340

• Allelic Composition: Ret^tm2.1Heno/Ret^tm2.1Heno
• Genetic Background: involves: C57BL/6 * FVB/N * SJL

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

nervous system

abnormal muscle spindle morphology ( J:132854 )

• reduced fusimotor innervation of muscle spindles

• muscle spindle innervation normal in Rectus femoris

abnormal motor neuron innervation pattern ( J:132854 )

• peroneal muscles totally lack both motor and sensory innervation in 42% of homozygotes

• 58% with normal peroneal innervation or with innervation absent only in the superficial peroneal muscles

• posterior Psoas major lacks innervation

• variable lack of innervation of Gluteus maximus, Tensor fascia latae, and Iliopsoas

decreased motor neuron number ( J:132854 )

• loss of more than 20% of motor neurons at the lumbar level

• elevated apoptosis of motor neurons between 13.5 and E15.5

muscle

abnormal hypaxial muscle morphology ( J:132854 )

abnormal gastrocnemius morphology ( J:132854 )

• reduced in size but with normal motor innervation

abnormal muscle spindle morphology ( J:132854 )

• reduced fusimotor innervation of muscle spindles

• muscle spindle innervation normal in Rectus femoris

muscular atrophy ( J:132854 )

• muscles lacking moter innervation display gross atrophy (peroneal, psoas major, tensor facia latae, etc)

limbs/digits/tail

abnormal gastrocnemius morphology ( J:132854 )

• reduced in size but with normal motor innervation