There are many different types of ataxia, with numerous causes. For example, ataxia can be genetic, occur due to an autoimmune response (e.g. gluten ataxia) or when we do not know whathas caused an individual’s ataxia, it is called “idiopathic”. If you fall into the last category, you might still turn out to have a genetic form. The genetic tests used to try and diagnose you may not have identified the abnormality present in your genes as yet. Genetic ataxias are caused by changes in the genetic code which eventually leads to symptoms of ataxia. Currently well known forms of genetic ataxias include the Spinocerebellar Ataxias (SCAs), Friedreich’s ataxia (FA), and Episodic Ataxia type 2 (EA2). Over the last three decades, laboratories all over the world have been discovering more forms of genetic ataxia.
Genetic testing has changed dramatically in recent years. An important breakthrough in genetic testing has been a technology called
whole genome sequencing (WGS). The new technologies enable hundreds of genes to be checked in individuals simultaneously (earlier, doctors used to check individual genes, sometimes one at a time, based on their clinical suspicions.) These advances have meant that cases previously designated as “idiopathic” ataxia have turned out to be of genetic cause. If you had genetic tests many years ago but did not receive a genetic diagnosis (and remain “idiopathic”), it might be worth being tested again. Even in middleaged and older individuals with idiopathic ataxia, new genetic forms of ataxia such as CANVAS and GAA-FGF14/SCA27B appear to account for
significant numbers.
As more ataxias have been identified, the chance of receiving a specific diagnosis through genetic testing has increased. This is becoming
increasingly important as treatments for the ataxias start entering clinical trials, and even in some cases being approved by the regulators. In order to access trials or treatments which could be relevant for you, it is important to have a specific diagnosis. Even now, there are a handful of targeted treatments available in inherited ataxias. Niemann Pick Type C (NPC), for example, is a condition which has ataxia as a symptom. There is already an approved treatment for NPC in the UK, and two more treatments were approved by the US regulators (the FDA) in 2024. NPC1 and NPC2 can be diagnosed by a genetic test. Treatments like these provide a justification for a GP or neurologist to arrange further genetic tests, especially in cases where genetic testing has not been carried out for many years.
Identifying the cause of ataxia in a family may enable individuals at risk of acquiring ataxia to undergo “pre-symptomatic” testing (if they so wish). In families where this information is known, younger generations can also make better-informed reproductive decisions.
If you have not received a specific diagnosis for your ataxia, and have not had genetic tests for many years, speak to your GP or neurologist about being tested again. If you have any questions about this, or want information about referrals to Specialist Ataxia Centres, please email the Ataxia UK Helpline at help@ataxia.org.uk.
