Phenotypes Associated with This Genotype

Genotype
MGI:3846848

• Allelic Composition: Npc1^spm/Npc1^spm
• Genetic Background: C57BLKS/J-Npc1^spm/J

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

mortality/aging

premature death ( J:6833 )

• lifespan is 12 to 14 weeks of age

behavior/neurological

tremors ( J:6833 )

• observed around 7 weeks of age and becomes more severe until death at 12 to 14 weeks of age

ataxia ( J:6833 )

• observed around 7 weeks of age and becomes more severe until death at 12 to 14 weeks of age

growth/size/body

weight loss ( J:6833 )

• begins around 7 weeks of age and continues until death at 12 to 14 weeks of age

enlarged liver ( J:7245 )

• Background Sensitivity: on this background this is seen as early as 4 weeks of age

enlarged spleen ( J:7245 )

• Background Sensitivity: on this background this is seen at 4 weeks of age

homeostasis/metabolism

sphingomyelinosis ( J:7245 )

• sphingomyelin is markedly elevated in liver and spleen but not in the brain

• sphingomyelinase activity is reduced by 70% in liver, 50% in spleen and 20%-30% in brain

abnormal cholesterol level ( J:7245 )

• markedly elevated levels are seen in the liver and spleen but not in the brain

• altered levels are detected in the liver of mice 4 weeks of age and older

increased liver cholesterol level ( J:7245 , J:102782 )

• approximately 4 times normal levels of cholesterol in the liver at 6 weeks of age (J:102782)

immune system

increased macrophage derived foam cell number ( J:7245 )

• large areas of the liver and spleen are replaced by foam cells

enlarged spleen ( J:7245 )

• Background Sensitivity: on this background this is seen at 4 weeks of age

liver/biliary system

enlarged liver ( J:7245 )

• Background Sensitivity: on this background this is seen as early as 4 weeks of age

increased liver cholesterol level ( J:7245 , J:102782 )

• approximately 4 times normal levels of cholesterol in the liver at 6 weeks of age (J:102782)

nervous system

Purkinje cell degeneration ( J:81305 , J:102782 )

• Purkinje cell loss at 45 days of age is significant in both the posterior lobe, and anterior lobe, by 60 days of age there is further loss, especially in the posterior lobe hemispheres, and by 90 days of age most Purkinje cells are gone, but some remain in the flocculus/paraflocculus, lobules IX and X of the nodular zone, and 3 stripes in the anterior zone. (J:81305)

• no loss is seen at 4 weeks of age, but by 6 weeks of age there is significant Purkinje cell loss, and loss is complete by 11 weeks of age (J:102782)

decreased Purkinje cell number ( J:7245 )

• cells are severely depleted in the brain

hematopoietic system

increased macrophage derived foam cell number ( J:7245 )

• large areas of the liver and spleen are replaced by foam cells

enlarged spleen ( J:7245 )

• Background Sensitivity: on this background this is seen at 4 weeks of age

cellular

increased macrophage derived foam cell number ( J:7245 )

• large areas of the liver and spleen are replaced by foam cells

abnormal plasma membrane sphingolipid content ( J:7245 )

• altered levels are present in liver from 4 weeks of age on

increased plasma membrane sphingolipid content ( J:7245 )

sphingomyelinosis ( J:7245 )

• sphingomyelin is markedly elevated in liver and spleen but not in the brain

• sphingomyelinase activity is reduced by 70% in liver, 50% in spleen and 20%-30% in brain

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Niemann-Pick disease		DOID:14504		J:6833