Phenotypes Associated with This Genotype

Genotype
MGI:3809430

• Allelic Composition: Col7a1^tm1Lbt/Col7a1^tm1Lbt
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6Crl

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

Col7a1^tm1Lbt/Col7a1^tm1Lbt mice develop blisters early after birth

mortality/aging

decreased survivor rate ( J:136145 )

• some mice fed a liquid diet survive longer than 100 days

postnatal lethality ( J:136145 )

• 67% die before weaning

• feeding mice a liquid diet from P10 improves survival and weight gain

limbs/digits/tail

abnormal autopod morphology ( J:136145 )

• at 80 days of age paws display dermal-epidermal separation, thickening of the epidermis, accumulation of connective tissue and decrease of elastic fibers in the dermis indicating strong dermal fibrosis

abnormal digit morphology ( J:136145 )

• beginning at 2 -3 weeks of age the paw condition worsens to include shortened or missing digits

• by 9 - 12 weeks of age partial or complete mitten deformities (pseudosyndactyly) are seen

• deformities are more severe on the forepaws than on the hindpaws

• deformities are the result of soft tissue accumulation and contraction not bone deformities

• severe contractures

digestive/alimentary system

abnormal tongue morphology ( J:136145 )

• blistering that results in malnutrition

growth/size/body

abnormal tongue morphology ( J:136145 )

• blistering that results in malnutrition

slow postnatal weight gain ( J:136145 )

• average weight at 2 - 3 weeks of age is about half that of control littermates and this difference is maintained until adolescence

• feeding mice a liquid diet from P10 improves survival and weight gain

skeleton

abnormal long bone morphology ( J:136145 )

• reduced mineral content in the long bones of the extremities

decreased bone mineral content ( J:136145 )

• reduced mineral content in the long bones of the extremities

craniofacial

abnormal tongue morphology ( J:136145 )

• blistering that results in malnutrition

integument

abnormal nail morphology ( J:136145 )

• beginning at 2 -3 weeks of age the paw condition worsens to include nail dystrophy

abnormal dermal layer morphology ( J:136145 )

• at 80 days of age paws show accumulation of connective tissue and decrease of elastic fibers in the dermis indicating strong dermal fibrosis

abnormal epidermal layer morphology ( J:136145 )

• hemidesmosomes are normal but few anchoring fibrils are present

thick epidermis ( J:136145 )

• relative thickening in the paws at 80 days of age

dermal-epidermal separation ( J:136145 )

• at 80 days of age paws display dermal-epidermal separation

blistering ( J:136145 )

• hemorrhagic subepidermal blisters form on the soles of the fore and hind paws within 24 - 48 hours after birth

• blisters occasionally form on the ears and mouth

• variable extent of blister formation

• splitting of the skin occurs below the lamina densa

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
recessive dystrophic epidermolysis bullosa		DOID:0060642	OMIM:226600	J:136145