[Tremor/ataxia syndrome related to Fragile X premutation].

The FXTAS syndrome (Fragile X-associated tremor/ataxia syndrome) is a specific neurodegenerative syndrome affecting subjects carrying a premutation of the FMR1 (fragile X mental retardation 1) gene. It affects mainly men with the premutation and aged more than 50 years. This syndrome is separate and distinct from the fragile X syndrome. The FXTAS syndrome remains underestimated today. It should be considered in patients older than 50 years with tremors and cerebellar ataxia, especially when Parkinson disease or cognitive disorders are present or when there is a family history of infertility, early menopause, or mental retardation. In these patients, hyperintense signals of mid-cerebellar peduncle images on T2 and FLAIR MRI justify genetic testing for the FMR1 premutation.