More symptom information
Learn more about specific symptoms of this leukodystrophy in these pages.
Giant Axonal Neuropathy (GAN) is a rare genetic disorder caused by mutations in the GAN1 gene leading to the accumulation of protein within axons. This does not allow signals to be transmitted properly, resulting in progressive neurological symptoms. Symptoms typically appear in childhood and include delayed development, loss of sensation, coordination and strength. Treatment mainly focuses on managing symptoms and providing supportive care to improve the individual’s quality of life.
A new diagnosis can be overwhelming as it brings unique challenges and adjustments, but it is important to remember that you are not alone.
Mutations of the GAN1 gene, which creates a protein called gigaxonin, are responsible for Giant Axonal Neuropathy. Gigaxonin breaks down neurofilaments which regulate the size of axons (axons allow neurons to communicate with other cells). When production of gigaxonin is disrupted, these neurofilaments are not broken down and become densely packed, causing axons to swell. These axons are then unable to transmit signals properly, causing the symptoms described.
Autosomal recessive: In autosomal recessive conditions, two copies of the genetic mutation are needed to cause the condition. We all have two copies of every gene, one from our mother and one from our father. The parents of someone with an autosomal recessive condition both carry one copy of the gene with a genetic mutation. Therefore, someone with an autosomal recessive condition has two copies of the genetic mutation, one copy from each parent. Each child of parents that both carry the genetic mutation will have a 25% chance of having the condition, a 50% chance of carrying the genetic mutation (like the parent), and a 25% chance of not having the condition.
Genetic counselling is essential for affected families due to the inheritance pattern of the condition. This is available at hospitals and Regional Genetic Centres. Please contact your doctor if you have any questions.
Learn more about genetic testing and counselling here.
Delayed development followed by clumsiness and unsteady walking are usually the first symptoms of GAN which presents usually before the age of 7 years.
Walking will become increasingly difficult, followed by numbness in the arms and legs and sometimes seizures. Speech problems, swallowing difficulties, hearing problems, abnormal vision and eye movements and cognitive difficulties often develop. Characteristically, those with GAN have dull, tightly curled hair of a different colour and texture to that of their parents.
Loss of ability to sweat, constipation and bladder problems as well as intolerance to heat are common.
Those with GAN experience worsening seizures, as well as symptoms such as paralysis and dementia. Most do not live past their 20s.
Learn more about specific symptoms of this leukodystrophy in these pages.
Although there is currently no specific treatment for this leukodystrophy, there is condition management information that may be useful for you in managing your or your loved one’s leukodystrophy.
There may be a current clinical trial, natural history study or patient registry for your condition. Check our current research page and ask your specialist doctor for more information.
We understand that research is a significant priority and source of hope for the leukodystrophy community. There is more research in leukodystrophy now than ever before. Alex TLC actively promotes and supports research in a number of ways.
Every month we update our database of research summaries with the most recent research. This includes summaries of leukodystrophy articles, clinical trials and pharmaceutical press releases. Our summaries allow our community to read about relevant recent research developments in a format that is easily understood.
Learn about the ways in which we can help in the how we support you section. When you or a family member been diagnosed with a leukodystrophy it may be difficult to know where to go for more advice – this information could help.
Our services and equipment section is here to help leukodystrophy patients and their families manage their condition. All information is based on our knowledge of UK services, however, our team are happy to receive support requests from other countries – email us.
You may be introduced to many different medical professionals which you may find confusing. View our guide to the health and care professionals you may encounter, with short descriptions about what they do.
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