Phenotypes associated with this allele

• Allele Symbol: Col2a1^Rgsc856
• Allele Name: RIKEN Genomic Sciences Center (GSC), 856
• Allele ID: MGI:3808759
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Col2a1^Rgsc856/Col2a1^Rgsc856	involves: C57BL/6JJcl * DBA/2JJcl	MGI:5007718
ht2	Col2a1^Rgsc856/Col2a1^+	involves: C57BL/6JJcl * DBA/2JJcl	MGI:3808761

Genotype
MGI:5007718

hm1

• Allelic Composition: Col2a1^Rgsc856/Col2a1^Rgsc856
• Genetic Background: involves: C57BL/6JJcl * DBA/2JJcl

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

Skeletal abnormalities in Col2a1^Rgsc856/Col2a1⁺ and Col2a1^Rgsc856/Col2a1^Rgsc856 mice at E18.5

mortality/aging

perinatal lethality, complete penetrance ( J:171906 )

• die at birth

skeleton

abnormal skeleton morphology ( J:171906 )

• severe skeletal dysplasia

abnormal pelvic girdle bone morphology ( J:171906 )

• severe pelvic hypoplasia

abnormal vertebrae morphology ( J:171906 )

• severe spondylar dysplasia

platyspondylia ( J:171906 )

abnormal chondrocyte morphology ( J:171906 )

• in the resting and proliferating zones chondrocytes have a spindle like shape

• in proliferating chondrocytes the rough ER is expanded

abnormal epiphyseal plate morphology ( J:171906 )

• total length of the growth plate is drastically reduced but the diameter is increased

• columnar alignment of proliferating chondrocytes is completely lost but hypertrophic chondrocytes are present

• drastic decrease in extracellular matrix in the proliferating zone

abnormal long bone epiphyseal plate proliferative zone ( J:171906 )

• at E18.5 in the proliferating zone of the femur, collagen fibers are markedly reduced and proteoglycan aggregates are reduced and irregular in size

• at E19.5 in the proliferating zone of the femur, type II collagen is barely detectable in the extracellular space and instead is mainly detected in the intracellular space, unlike in wild-type mice

abnormal chondrocyte physiology ( J:171906 )

• expression analysis indicates an increase in ER stress in rib cartilage at E18.5

growth/size/body

short snout ( J:171906 )

decreased fetal size ( J:171906 )

• severe dwarfism

craniofacial

short snout ( J:171906 )

limbs/digits/tail

brachydactyly ( J:171906 )

short limbs ( J:171906 )

• extremely shortened limbs

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
spondyloepimetaphyseal dysplasia		DOID:0080027		J:171906

Genotype
MGI:3808761

ht2

• Allelic Composition: Col2a1^Rgsc856/Col2a1⁺
• Genetic Background: involves: C57BL/6JJcl * DBA/2JJcl

Skeletal abnormalities in Col2a1^Rgsc856/Col2a1⁺ and Col2a1^Rgsc856/Col2a1^Rgsc856 mice at E18.5

skeleton

skeleton phenotype ( J:171906 )

N • unlike mice with heterozygous for Col2a1^Dmm, mice do not display more severe articular cartilage degeneration compared to age matched controls

short humerus ( J:133634 )

• most heterozygous mutant mice exhibit forelimb rhizomelia, or shortening of the humerus

short radius ( J:133634 )

• in more severe cases, the radius and ulna are affected, as well as the humerus

short ulna ( J:133634 )

• in more severe cases, the radius and ulna are affected, as well as the humerus

short femur ( J:171906 )

vertebral body hypoplasia ( J:171906 )

• slightly hypoplastic

abnormal chondrocyte morphology ( J:171906 )

• in proliferating chondrocytes the rough ER is expanded

abnormal epiphyseal plate morphology ( J:171906 )

• columnar alignment of proliferating chondrocytes is disordered with reduced extracellular matrix spaces

abnormal long bone epiphyseal plate proliferative zone ( J:171906 )

• collagen fibers in the proliferating zone of the femur seem to be slightly less dense

abnormal chondrocyte physiology ( J:171906 )

• expression analysis indicates an increase in ER stress in rib cartilage at E18.5

growth/size/body

decreased fetal size ( J:171906 )

• mildly but significantly smaller than wild-type controls at E18.5

limbs/digits/tail

abnormal forelimb morphology ( J:133634 )

short humerus ( J:133634 )

• most heterozygous mutant mice exhibit forelimb rhizomelia, or shortening of the humerus

short radius ( J:133634 )

• in more severe cases, the radius and ulna are affected, as well as the humerus

short ulna ( J:133634 )

• in more severe cases, the radius and ulna are affected, as well as the humerus

abnormal hindlimb morphology ( J:133634 )

• in severe cases, the hindlimbs are shortened, as well as the forelimbs

short femur ( J:171906 )

short limbs ( J:133634 )

• in severe cases, all four limbs are shortened

micromelia ( J:171906 )