[Fragile X-associated tremor/ataxia syndrome]

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a recently characterized adult onset neurodegenerative disorder affecting both male and female (male>female) carriers of premutation CGG repeat expansions of the FMR1 gene. Onset typically occurs after the age of 50 years with a lifetime risk of FXTAS in males of about 1 in 3,000-6,000. Core features include progressive gait ataxia and cerebellar tremor with associated features of cognitive deficits, peripheral neuropathy and dysautonomia. The diagnosis of FXTAS is established based on clinical presentation, cerebral imaging and genetic testing. Due to the still low level of awareness of FXTAS and its variable clinical picture FXTAS is substantially underdiagnosed. However, confirming the diagnosis is essential for genetic counseling of the patients as the offspring are at risk for fragile X syndrome, premature ovarian insufficiency (POI) or FXTAS. Furthermore, many features of FXTAS can be treated symptomatically.