From: Mouse models of the fragile X premutation and fragile X-associated tremor/ataxia syndrome
Pathology | Human FXTAS | CGG knock-in mouse |
---|---|---|
CGG trinucleotide repeat length | 55 to 199 CGG repeat length, repeat instability | 70 to 300 CGG repeats, modest repeat instability |
Elevated FMR1 mRNA expression | Increased 2- to 8-fold | Increased 1.5- to 3-fold |
Fragile X mental retardation protein levels | Reduced in several brain regions | Reduced in several brain regions |
Motor impairments | Tremor/ataxia, postural sway, parkinsonism | Impaired on rotarod and ladder rung task |
Cognitive Impairments | Poor working memory, anxiety, depression, social phobia | Spatial memory deficits, altered anxiety-like behaviors |
Intranuclear inclusions | Neurons and astrocytes, highly correlated with CGG repeat length, frequency increases with age | Neurons and astrocytes, related to length of CGG repeat, frequency increases with age |