Hereditary ataxias (HA) include a wide variety of inherited diseases where the main symptom is ataxia. Ataxia refers to uncoordinated, clumsy movements and walking problems with loss of balance. Changes in certain genes cause HA. In most cases, the disease affects more than one family member; however, sometimes there is no family history at all. In HA, ataxia is usually not the only symptom. Other neurological signs may include: • Slowness and shaking (tremor) • Twisting, turning or other uncontrolled movement (dystonia) • Impaired sensation such as numbness, tingling and burning in legs and arms, with or without muscle weakness (neuropathy) Other organs may also be affected, such as the heart (cardiomyopathy) or the eyes (retinopathy).