Abstract
Carriers of an FMR1 premutation allele (55-200 CGG repeats) often develop the neurodegenerative disorders, fragile X-associated tremor/ataxia syndrome (FXTAS). Neurological signs of FXTAS, parkinsonism and rapid onset of cognitive decline have not been reported in individuals with an unmethylated full mutation (FM). Here, we report a Chilean family affected with FXS, inherited from a parent carrier of an FMR1 unmethylated full mosaic allele, who presented with a fast progressing FXTAS. This case suggests that the definition of FXTAS may need to be broadened to not only include those with a premutation but also those with an expanded allele in FM range with a lack of methylation leading to elevated FMR1-mRNA expression levels and subsequent RNA toxicity.
Original language | English (US) |
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Pages (from-to) | 378-382 |
Number of pages | 5 |
Journal | Clinical Genetics |
Volume | 86 |
Issue number | 4 |
DOIs | |
State | Published - 2014 |
Keywords
- Fragile X
- FXTAS
- Parkinsonism
- Unmethylated full mutation
ASJC Scopus subject areas
- Genetics(clinical)
- Genetics