Friedreich’s ataxia is a neurodegenerative disorder characterized by progressive gait and limb ataxia, dysarthria, dysphagia, oculomotor dysfunction, loss of deep tendon reflexes, pyramidal tract signs, scoliosis, and in some, cardiomyopathy, diabetes mellitus, visual loss, and defective hearing. Friedreich’s ataxia is the most common early-onset hereditary ataxia, accounting for approximately 50% of all cases of hereditary ataxia. The prevalence of FRDA is estimated to be between 1 in 22,000 to 2 in 100,000. Symptoms typically begin between the ages of 5 and 15 years, although sometimes they appear in adulthood and on rare occasions as late as age 75. Patients who develop Friedreich ataxia between ages 26 and 39 are considered to have late-onset Friedreich ataxia (LOFA), while patients who develop the symptoms after age of 40 they are considered to have very late-onset Friedreich ataxia (VLOFA).
Friedreich's ataxia is caused by mutations in the FXN gene.