Phenotypes associated with this allele

• Allele Symbol: Mnat1^tm2Tpm
• Allele Name: targeted mutation 2, Tomi P Makela
• Allele ID: MGI:3707001
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Mnat1^tm2Tpm/Mnat1^tm2Tpm	Not Specified	MGI:3707423
cn2	Egr2^tm2(cre)Pch/? Mnat1^tm2Tpm/Mnat1^tm2.1Tpm	involves: 129S2/SvPas	MGI:3707557

Genotype
MGI:3707423

hm1

• Allelic Composition: Mnat1^tm2Tpm/Mnat1^tm2Tpm
• Genetic Background: Not Specified

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

normal phenotype

no abnormal phenotype detected ( J:120170 )

• healthy and fertile

Genotype
MGI:3707557

cn2

• Allelic Composition: Egr2^tm2(cre)Pch/?; Mnat1^tm2Tpm/Mnat1^tm2.1Tpm
• Genetic Background: involves: 129S2/SvPas

reproductive system

abnormal spermatogenesis ( J:120170 )

♂ • at 6 weeks of age, pyknotic germ cells in the seminiferous tubules in testis indicative of spermatogonia and spermatocyte cell death

♂ • at 10 weeks of age, severe wasting and dramatically reduced cellularity was visible macroscopically; entirely devoid of all germ cells and their derivatives

♂ • at 3 weeks of age, the developing germ lineage in the seminiferous tubules was completely indistinguishable from control animals

♂ • at 10 weeks of age, Sertoli cells in the seminiferous tubules and cells of interstitium were normal

behavior/neurological

abnormal gait ( J:120170 )

• exhibit a variety of symptoms of Schwann cell dysfunction including gait abnormalities beginning at 3 month of age

• mutant were viable and healthy and displayed no signs of neuropathy or myelin dysfunction into early adulthood up to 3 month of age

growth/size/body

decreased lean body mass ( J:120170 )

• beginning at 3 month of age, pronounced in the hind limbs suggestive of neuropathy and subsequent neurogenic muscular atrophy

nervous system

abnormal Schwann cell precursor morphology ( J:120170 )

• at 3 months of age, the mutant exhibited a marked increase in Schwann lineage proliferation

demyelination ( J:120170 )

• beginning at 3 month of age, large diameter axons completely denuded of myelin are present in sciatic nerves

• by 5 month of age, essentially all of the myelinated axons shows signs of extensive demyelination

• sciatic nerves from mutant animals at 1 month and 2 month of age showed normal myelin thickness compared to axonal diameter indicating myelinating Schwann cells are capable of attaining and a mature myelinated phenotype