Phenotypes associated with this allele

• Allele Symbol: Sgcg^tm1Mcn
• Allele Name: targeted mutation 1, Elizabeth M McNally
• Allele ID: MGI:2154693
• Summary: 4 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Sgcg^tm1Mcn/Sgcg^tm1Mcn	involves: 129X1/SvJ * C57BL/6	MGI:3037288
cx2	Ltbp4^dmod1-129T2/SvEmsJ/Ltbp4^dmod1-129T2/SvEmsJ Sgcg^tm1Mcn/Sgcg^tm1Mcn	129T2.Cg-Ltbp4^dmod1-129T2/SvEmsJ Sgcg^tm1Mcn	MGI:4414766
cx3	Ltbp4^dmod1-DBA/2J/Ltbp4^dmod1-DBA/2J Sgcg^tm1Mcn/Sgcg^tm1Mcn	D2.Cg-Ltbp4^dmod1-DBA/2J Sgcg^tm1Mcn	MGI:4414767
cx4	Itga7^tm1Umr/Itga7^tm1Umr Sgcg^tm1Mcn/Sgcg^tm1Mcn	involves: 129S1/Sv * 129X1/SvJ * C57BL/6	MGI:3583814

Genotype
MGI:3037288

hm1

• Allelic Composition: Sgcg^tm1Mcn/Sgcg^tm1Mcn
• Genetic Background: involves: 129X1/SvJ * C57BL/6

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

Stunted growth and abnormal stance in Sgcg^tm1Mcn/Sgcg^tm1Mcn mice

mortality/aging

premature death ( J:49871 )

• about 50% were dead by 5 months of age, 10% died by 3 weeks

behavior/neurological

behavior/neurological phenotype ( J:57664 )

N • responded well in swimming tests at 7 weeks of age

N • baseline activity levels improved after exercise

abnormal gait ( J:49871 )

• stiff walking gait with widened hind-leg spacing

decreased locomotor activity ( J:49871 )

• less activity in general but particularly climbing and burrowing

• slow to initiate walking or running activity from a sitting position

cardiovascular system

decreased heart weight ( J:49871 )

• heart mass is reduced but heart to body weight ratio is increased due to smaller body size

abnormal heart ventricle morphology ( J:49871 )

• fibrosis is present in ventricles

thick ventricular wall ( J:49871 )

• right and left ventricular walls are thickened by 20 weeks of age and the ventricular cavities nearly obliterated

coronary artery spasm ( J:88456 )

• microvascular filling defects are seen involving coronary arteries

• coronary vasospasms increase with exercise

growth/size/body

decreased body weight ( J:49871 , J:57664 )

• body weight was normal at 8 weeks but was low by 20 weeks (J:49871)

• weight gain improved when animals were forced to exercised (J:57664)

homeostasis/metabolism

increased circulating creatine kinase level ( J:49871 , J:57664 )

• elevated serum creatine kinase levels at 2 weeks to as much as 240X by 8 weeks of age (J:49871)

• levels of serum creatine kinase improved in animals forced to exercise (J:57664)

muscle

muscle phenotype ( J:57664 )

N • not susceptible to contraction induced injury

abnormal diaphragm morphology ( J:49871 )

• diaphragm muscle hypertrophied and opaque

thick diaphragm muscle ( J:49871 )

• although thickened, the diaphragm contains no more or larger myofibers

dystrophic muscle ( J:49871 )

• severe dystrophic changes seen

• variable fiber size

• inflammatory infiltrate

• abnormal calcification with fatty and fibrouse replacement

• changes seen in the quadriceps, and gastrocnemius where degenerate and intact muscle segments are juxtaposed in additon to the diaphragm

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
autosomal recessive limb-girdle muscular dystrophy type 2C		DOID:0110277	OMIM:253700	J:49871 , J:57664 , J:88456

Genotype
MGI:4414766

cx2

• Allelic Composition: Ltbp4^{dmod1-129T2/SvEmsJ}/Ltbp4^{dmod1-129T2/SvEmsJ}; Sgcg^tm1Mcn/Sgcg^tm1Mcn
• Genetic Background: 129T2.Cg-Ltbp4^{dmod1-129T2/SvEmsJ} Sgcg^tm1Mcn

muscle

skeletal muscle fibrosis ( J:155107 )

• Background Sensitivity: null mice on the 129T2/SvEmsJ background have less hydroxyproline content, a reflection of the degree of fibrosis, than null mice on the DBA/2J background

abnormal muscle physiology ( J:155107 )

• Background Sensitivity: null mice on the 129T2/SvEmsJ background have less muscle membrane leakage, as measured by Evans Dye leakage, than null mice on the DBA/2J background

behavior/neurological

increased grip strength ( J:155107 )

• Background Sensitivity: null mice in the 129T2/SvEmsJ background are stronger than null mice in the DBA/2J background

Genotype
MGI:4414767

cx3

• Allelic Composition: Ltbp4^dmod1-DBA/2J/Ltbp4^dmod1-DBA/2J; Sgcg^tm1Mcn/Sgcg^tm1Mcn
• Genetic Background: D2.Cg-Ltbp4^dmod1-DBA/2J Sgcg^tm1Mcn

muscle

skeletal muscle fibrosis ( J:155107 )

• Background Sensitivity: null mice on the DBA/2J background have less hydroxyproline content, a reflection of the degree of fibrosis, than null mice on the 129T2/SvEmsJ background

abnormal muscle physiology ( J:155107 )

• Background Sensitivity: null mice on the DBA/2J background have greater muscle membrane leakage, as measured by Evans Dye leakage, than null mice on the 129T2/SvEmsJ background

behavior/neurological

decreased grip strength ( J:155107 )

• Background Sensitivity: null mice in the DBA/2J background are weaker than null mice in the 129T2/SvEmsJ background

Genotype
MGI:3583814

cx4

• Allelic Composition: Itga7^tm1Umr/Itga7^tm1Umr; Sgcg^tm1Mcn/Sgcg^tm1Mcn
• Genetic Background: involves: 129S1/Sv * 129X1/SvJ * C57BL/6

mortality/aging

lethality at weaning, complete penetrance ( J:91880 )

• average life span 21 days

• nearly all dead by 25 days of age

behavior/neurological

decreased grooming behavior ( J:91880 )

• little or no grooming behavior

abnormal stationary movement ( J:91880 )

• reduced mobility

abnormal gait ( J:91880 )

• display a "hopping" gait

muscle

muscle degeneration ( J:91880 )

• severe skeletal muscle degeneration, widespread rather than focal

• ongoing necrosis accompanied by regeneration

growth/size/body

postnatal growth retardation ( J:91880 )

• smaller size than controls

• weighed half as much as controls by 25 days of age

skeleton

kyphoscoliosis ( J:91880 )

cellular

abnormal cell physiology ( J:91880 )

• enhance muscle cell membrane permeability

increased apoptosis ( J:91880 )