Fragile X-Associated Tremor / Ataxia Syndrome (FXTAS) By Hector A Gonzalez-Usigli, MD, HE UMAE Centro Médico Nacional de Occidente Reviewed / Revised Feb 2022 | Modified Sep 2022 View Patient Education Symptoms and Signs Diagnosis Treatment Key Points Fragile X-associated tremor / ataxia syndrome is a genetic disorder affecting mostly men and causing tremor, ataxia, and dementia.