Phenotypes associated with this allele

• Allele Symbol: Isl2^tm2Slp
• Allele Name: targeted mutation 2, Samuel L Pfaff
• Allele ID: MGI:3046260
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Isl2^tm2Slp/Isl2^tm2Slp	involves: 129S1/Sv	MGI:3046280
cx2	Mnx1^tm1Jhk/Mnx1^tm1Jhk Isl2^tm2Slp/Isl2^tm2Slp	involves: 129P2/OlaHsd * 129S1/Sv	MGI:3688256

Genotype
MGI:3046280

hm1

• Allelic Composition: Isl2^tm2Slp/Isl2^tm2Slp
• Genetic Background: involves: 129S1/Sv

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

mortality/aging

neonatal lethality, complete penetrance ( J:89755 )

• most homozygotes die within 24 hours of birth

growth/size/body

distended abdomen ( J:89755 )

• severely distended abdomen after birth

nervous system

abnormal innervation ( J:89755 )

• bridging between segmentally arrayed motor nerves occurs

abnormal motor neuron morphology ( J:89755 )

• depletion of visceral motor neurons without an increase in somatic motor neurons

• appearance of atypical and ectopic somatic-like neurons

• small nuclei more like visceral than somatic motor neuron nuclei

abnormal neuron specification ( J:89755 )

• early stages of spinal motor neuron differentiation normal

• ectopic localization for some neurons

• tight columnar organization in thoracic region disrupted with intermingling of medial and lateral divisions

Genotype
MGI:3688256

cx2

• Allelic Composition: Mnx1^tm1Jhk/Mnx1^tm1Jhk; Isl2^tm2Slp/Isl2^tm2Slp
• Genetic Background: involves: 129P2/OlaHsd * 129S1/Sv

nervous system

abnormal axon guidance ( J:89755 )

• frequently observe inappropriate axonal bridges between segmentally arrayed motor nerves indicating defects in motor axon guidance

abnormal motor neuron morphology ( J:89755 )

• exhibit a complete absence of Nos1+ preganglionic motor column neurons

abnormal motor neuron innervation pattern ( J:89755 )

• exhibit motor axon projections into the periphery

cellular

abnormal axon guidance ( J:89755 )

• frequently observe inappropriate axonal bridges between segmentally arrayed motor nerves indicating defects in motor axon guidance