Phenotypes associated with this allele

• Allele Symbol: Mdfi^tm1Krt
• Allele Name: targeted mutation 1, Norbert Kraut
• Allele ID: MGI:2155446
• Summary: 3 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Mdfi^tm1Krt/Mdfi^tm1Krt	B6.129S4-Mdfi^tm1Krt	MGI:2176464
hm2	Mdfi^tm1Krt/Mdfi^tm1Krt	involves: 129S4/SvJaeSor	MGI:2176463
hm3	Mdfi^tm1Krt/Mdfi^tm1Krt	involves: 129S4/SvJaeSor * C57BL/6	MGI:2176462

Genotype
MGI:2176464

hm1

• Allelic Composition: Mdfi^tm1Krt/Mdfi^tm1Krt
• Genetic Background: B6.129S4-Mdfi^tm1Krt

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

mortality/aging

embryonic lethality during organogenesis, complete penetrance ( J:50877 )

• death around E10.5; complete penetrance

• Background Sensitivity: complete penetrance of lethality at E10.5, unlike on a mixed 129S4/SvJaeSor and C57BL/6 background in which there is partial penetrance, and on a 129S4/SvJaeSor background in which 75% survive to adulthood and 25% die postnatally

embryo

incomplete embryo turning ( J:50877 )

• most embryos at E9.5 have not completed turning

embryonic growth retardation ( J:50877 )

• developmental retardation is seen at E9.5; most embryos have not completed turning

wavy neural tube ( J:50877 )

• more than 50% of embryos exhibit an undulated neural tube

decreased trophoblast giant cell number ( J:50877 )

• decrease in the numbers of trophoblast giant cells, due to a higher rate of apoptosis

nervous system

wavy neural tube ( J:50877 )

• more than 50% of embryos exhibit an undulated neural tube

growth/size/body

embryonic growth retardation ( J:50877 )

• developmental retardation is seen at E9.5; most embryos have not completed turning

Genotype
MGI:2176463

hm2

• Allelic Composition: Mdfi^tm1Krt/Mdfi^tm1Krt
• Genetic Background: involves: 129S4/SvJaeSor

mortality/aging

postnatal lethality, incomplete penetrance ( J:50877 )

• 25% (those with the most severe skeletal defects) die by P7

• Background Sensitivity: mice on the 129S4/SvJaeSor background survive much longer than on a C57BL/6 or mixed 129S4/SvJaeSor and C57BL/6 backgrounds

growth/size/body

decreased body size ( J:50877 )

• 75% of mutants with skeletal defects have an average 20% reduction in size and weight

limbs/digits/tail

curly tail ( J:50877 )

• vertebral bodies sometimes fuse laterally in the tail region giving rise to kinky and/or curly tails

kinked tail ( J:50877 )

• vertebral bodies sometimes fuse laterally in the tail region giving rise to kinky and/or curly tails

respiratory system

respiratory distress ( J:50877 )

• respiratory distress is seen in the 25% of mice that die postnatally, most likely due to rib defects

skeleton

abnormal axial skeleton morphology ( J:50877 )

• vertebral and rib defects in 90% of mice

• however, the craniofacial and appendicular skeleton is normal

abnormal sternocostal joint morphology ( J:50877 )

• truncated ribs fail to attach to the sternum

abnormal rib morphology ( J:50877 )

• rib defects are apparent at E13.5

decreased rib number ( J:50877 )

• occasionally, mutants show loss or one or more ribs

rib bifurcation ( J:50877 )

• rib defects include bifurcations in the distal regions of the ribs on both side of the sternum

rib fusion ( J:50877 )

• rib defects include fusions in the distal regions of the ribs on both side of the sternum

truncated ribs ( J:50877 )

• rib defects include truncated ribs that fail to attach to the sternum

abnormal vertebral spinous process morphology ( J:50877 )

• spinous processes fail to fuse medially in the lumbar and sacral region in newborns and instead often fuse in a cranial to caudal direction

abnormal vertebral body morphology ( J:50877 )

• vertebral bodies sometimes fuse laterally in the tail region

abnormal sclerotome morphology ( J:50877 )

• marker analysis indicates that the lateral and ventromedial sclerotome shows defective development, while the medioventral region develops normally

nervous system

delayed neural tube closure ( J:50877 )

• embryos at E11.5 show a delay in the closure of the cranial neural tube

spina bifida ( J:50877 )

• spinous processes fail to fuse medially in the lumbar and sacral region in newborns, resulting in a mild form of spinal bifida

embryo

delayed neural tube closure ( J:50877 )

• embryos at E11.5 show a delay in the closure of the cranial neural tube

spina bifida ( J:50877 )

• spinous processes fail to fuse medially in the lumbar and sacral region in newborns, resulting in a mild form of spinal bifida

Genotype
MGI:2176462

hm3

• Allelic Composition: Mdfi^tm1Krt/Mdfi^tm1Krt
• Genetic Background: involves: 129S4/SvJaeSor * C57BL/6

mortality/aging

embryonic lethality during organogenesis, incomplete penetrance ( J:50877 )

• about 2/3 of mutants die around E10.5

• Background Sensitivity: penetrance of lethality is less than on a C57BL/6 congenic background, however mutants that die at E10.5, die much sooner than on a 129S4/SvJaeSor background