Phenotypes associated with this allele

• Allele Symbol: Sostdc1^tm1Snd
• Allele Name: targeted mutation 1, Scott Saunders
• Allele ID: MGI:5617872
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Sostdc1^tm1Snd/Sostdc1^tm1Snd	involves: C57BL/6	MGI:5770346
cx2	Lrp5^tm1Kry/Lrp5^tm1Kry Sostdc1^tm1Snd/Sostdc1^tm1Snd	involves: 129S1/Sv * 129X1/SvJ * C57BL/6	MGI:5770364

Genotype
MGI:5770346

hm1

• Allelic Composition: Sostdc1^tm1Snd/Sostdc1^tm1Snd
• Genetic Background: involves: C57BL/6

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

Characterization of the osteoblast and chondrocyte phenotype in Sostdc1^tm1Snd/Sostdc1^tm1Snd mutants

mortality/aging

mortality/aging ( J:216098 )

N • homozygotes are viable

N • Background Sensitivity: on a 129/SvEv genetic background litter sizes are often reduced and there is a frequent increase in the number of resorptions

skeleton

decreased chondrocyte proliferation ( J:216098 )

• at P0, proliferation of round proliferative chondrocytes is decreased by 62% as shown by BrdU labeling

• however, no significant change is noted in flat proliferative, prehypertrophic or hypertrophic chondrocytes

abnormal osteoblast physiology ( J:216098 )

• at 2.5 months of age, osteoblast bone formation rate is increased by 38%

increased osteoblast proliferation ( J:216098 )

• at 1.5 months of age, active trabecular osteoblast proliferation of long bones is significantly increased by 2.9-fold

decreased osteoclast cell number ( J:216098 )

• at 2.5 months of age, the number of trabecular osteoclast cells is decreased by 58%

increased bone mineral content ( J:216098 )

• whole body mineral content (BMC) is increased significantly only at 2.5 months, with no significant changes in BMC at 1.5 months or at 3 months of age

increased bone mineral density ( J:216098 )

• between 1.5 to 3.0 months of age, homozygotes show a significant increase (7.5-11.6%) in whole body bone mineral density (BMD) relative to wild-type controls

• however, by 4 months of age the increase in BMD normalizes and is restored to wild-type levels

• Background Sensitivity: transient increase in BMD is more severe on a C57BL/6 genetic background than on a 129/SvEv background

increased trabecular bone volume ( J:216098 )

• trabecular bone volume is significantly increased at 1.5 and 2.5 months

increased osteoblast cell number ( J:216098 )

• at 1.5 months of age, the number of active trabecular osteoblasts is increased by 2-fold

increased bone mass ( J:216098 )

• increases in bone mass seen at 1.5 and 3 months are not due to significant increases in whole body bone mineral content

abnormal bone ossification ( J:216098 )

• at 2.5 months of age, osteoblast bone formation rate is increased by 38%

abnormal bone mineralization ( J:216098 )

• increased mineralization of phalanges in both the fore- and hindlimbs, clearly evident in digits 4 and 5 and fully penetrant at P0

hematopoietic system

decreased osteoclast cell number ( J:216098 )

• at 2.5 months of age, the number of trabecular osteoclast cells is decreased by 58%

immune system

decreased osteoclast cell number ( J:216098 )

• at 2.5 months of age, the number of trabecular osteoclast cells is decreased by 58%

cellular

decreased chondrocyte proliferation ( J:216098 )

• at P0, proliferation of round proliferative chondrocytes is decreased by 62% as shown by BrdU labeling

• however, no significant change is noted in flat proliferative, prehypertrophic or hypertrophic chondrocytes

abnormal osteoblast physiology ( J:216098 )

• at 2.5 months of age, osteoblast bone formation rate is increased by 38%

increased osteoblast proliferation ( J:216098 )

• at 1.5 months of age, active trabecular osteoblast proliferation of long bones is significantly increased by 2.9-fold

Genotype
MGI:5770364

cx2

• Allelic Composition: Lrp5^tm1Kry/Lrp5^tm1Kry; Sostdc1^tm1Snd/Sostdc1^tm1Snd
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6

skeleton

skeleton phenotype ( J:216098 )

N • at 1.5 months of age, active trabecular osteoblast numbers normalize to wild-type levels