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16 | InTouch SPRING 2023 Ataxia means ‘lack of coordination’ and it is a symptom of many conditions. Inherited ataxia is an umbrella term for a group of rare genetic disorders characterised by slowly progressive incoordination of gait that is often associated with poor coordination of hands, speech, and eye movements. Frequently, atrophy (wasting) of a part of the brain called the cerebellum occurs. The cerebellum is where movement, posture, and balance are coordinated. MDANZ covers all types of inherited ataxias. These rare conditions include Friedreich’s ataxia (FA), all subtypes of spinocerebellar ataxia (SCA), and a condition called cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS). Symptoms There are many different types of hereditary ataxias and each may have unique signs and symptoms. However, in general, it is difficult to differentiate among the different types, and all are characterised by problems with movement that tend to get worse over time. Affected people may experience the following: • Problems with coordination and balance (ataxia) • Uncoordinated walk • Poor hand-eye coordination • Speech difficulties (dysarthria) • Involuntary eye movements • Vision problems Inherited Ataxias YOUR CONDITION IN REVIEW • Difficulty processing, learning, and remembering information. Depending on the type of condition, signs and symptoms can develop anytime from childhood to late adulthood. Over time, the affected nerve cells begin to function poorly and ultimately degenerate. As the disease progresses, muscles become less and less responsive to commands from the brain, causing coordination problems to become more pronounced. Those affected by poor coordination will notice poor balance when walking, inability to run, clumsiness of the hands, a change in speech, or unusual eye movements. Individuals with inherited ataxias may develop a variety of other symptoms as their condition progresses, such as numbness and tingling or pain in the arms and legs (sensory neuropathy), uncontrolled muscle tensing (dystonia), muscle wasting (atrophy), muscle twitches (fasciculations), rigidity, tremors, seizures, tinnitus, vertigo, and/or involuntary jerking movements (chorea). The condition may be complicated by vision disorders and eye movement paralysis, or have an association with heart disease, breathing problems, bone abnormalities, and/or diabetes, depending on the type. FA is associated with cardiac problems, depression, and type 2 diabetes. Cardiac complications include cardiomyopathy, myocardial fibrosis, heart failure, tachycardia, or heart block. Many of these symptoms can be treated with medication. Cause Mutations in many different genes are known to cause spinocerebellar ataxia (SCA). In the most prevalent subtypes, the causative gene has been identified, while in others, the genetic cause is still unknown. The genetic cause for Friedreich ataxia was discovered in 1996 in a gene on chromosome 9 called ‘frataxin’. This was more than 120 years after Nikolaus Friedreich (1825- 1882) first described the disease in Heidelberg, Germany. CANVAS was only first described in 2011, and in 2019 it was established that an alteration in a gene called The genetic cause for Friedreich ataxia was discovered in 1996 in a gene on chromosome 9 called ‘frataxin’. This was more than 120 years after Nikolaus Friedreich (1825-1882) first described the disease in Heidelberg, Germany.