What is Friedreich's Ataxia?

Overview 

Friedreich's ataxia is an inherited, progressive neurological disorder that primarily affects the nervous system and the heart. This article will delve into the main causes of Friedreich’s Ataxia, the signs and symptoms, and management options. 

Causes of friedreich's ataxia

Friedreich’s ataxia is caused by a mutation in the FXN gene, which provides instructions for cells to make a protein called frataxin. This protein is involved in the regulation of iron within cells, and a frataxin deficiency leads to dysfunction in the nervous system, heart, and other organs.

Friedreich's ataxia is inherited in an autosomal recessive pattern, which means that a person must inherit two copies of the mutated FXN gene (one from each parent) to develop the disorder. If a person inherits only one mutated copy of the gene, they are considered a carrier of the condition, meaning they can pass it on but do not experience symptoms.

In some cases, a person with Friedreich's ataxia may not have a family history of the disorder. This can occur when the FXN gene mutates during the formation of reproductive cells or early in foetal development.¹

Overall, the primary cause of Friedreich's ataxia is a genetic mutation that affects the production of frataxin, leading to iron accumulation, oxidative stress, and dysfunction in various organs, particularly the nervous system and heart.

Signs and symptoms of Friedreich's ataxia

Friedreich's ataxia is a progressive disorder, and its symptoms can vary widely, even between people in the same family.² However, the most common signs and symptoms of the disorder include:

• Ataxia: a loss of coordination and balance is the most common symptom of Friedreich's ataxia, affecting both the arms and legs. This can lead to difficulty with walking, fine motor skills, and maintaining good posture
• Muscle weakness: you may experience weakness in your arms and legs, which can make you struggling with daily activities like climbing stairs and lifting objects
• Sensory loss: you may experience loss of sensation in your hands and feet, or loss of vision and hearing
• Slurred speech: Friedreich’s ataxia may lead to poor control of the muscles involved in speaking, making speech difficult to understand
• Cardiomyopathy: Friedreich's ataxia can cause damage to the heart muscle, leading to a condition called cardiomyopathy. This can result in an irregular heartbeat, shortness of breath, and chest pain
• Diabetes: you may develop diabetes if Friedreich’s ataxia causes damage in the pancreas (which produces insulin, the hormone that regulates blood sugar) 

Management and treatment for Friedreich's ataxia

Friedreich’s ataxia itself cannot be cured. However, it is possible to treat the symptoms and conditions it causes. Here are some treatment options as well as the symptoms they can help: 

• Physical therapy to improve muscle strength and coordination 
• Occupational therapy to help with daily tasks by finding alternative ways to do them 
• Medications to manage symptoms like tremors and muscle stiffness 
• Surgery to correct spinal abnormalities (such as scoliosis)
• Healthy lifestyle and diet 

Diagnosis of Friedreich's ataxia

Your doctor will review your medical history and perform a thorough physical examination, which includes a detailed neuromuscular assessment. During this exam, your doctor will check for any issues with your nervous system, such as poor balance, lack of reflexes, and decreased sensation in your arms and legs, which may spread to other parts of your body, including joints.

Other diagnostic tests may include:

• CT or MRI scans of the brain and spinal cord to rule out other neurological conditions
• X-rays of your head, spine and chest
• Genetic testing to identify if you have the mutated FXN gene
• Electromyography to measure the electrical activity in your muscle cells
• Nerve conduction studies to determine how quickly your nerves send impulses
• Eye exams to evaluate the health of your optic nerve
• Echocardiograms or electrocardiograms to diagnose heart disease

Risk factors

Friedreich's ataxia is a genetic disorder, which means that it is caused by mutations in specific genes. Therefore, the primary risk factor for the condition is having a family history of Friedreich's ataxia. 

In rare cases, Friedreich's ataxia may also occur as a result of a new mutation in the FXN gene, rather than being inherited from a parent. However, this is much less common.

There are no known environmental or lifestyle risk factors for Friedreich's ataxia. 

Complications

Friedreich's ataxia worsens over time, and many individuals with the disorder rely on a wheelchair approximately 15 to 20 years after symptoms first appear. Those with advanced ataxia may lose the ability to walk altogether.

Heart disease is the leading cause of death for people with Friedreich's ataxia, and it can become fatal by early adulthood. Individuals with mild ataxia symptoms typically live longer.

Late-onset Friedreich's ataxia, which develops at age 25 or later, generally leads to a milder form of the disease characterised by a slower decline.

Around 10% of those with Friedreich's ataxia develop diabetes, and other complications may include heart failure, scoliosis, and difficulty digesting carbohydrates.

FAQs

How can I prevent Friedreich's ataxia?

Friedreich's ataxia cannot be prevented since it is a genetic disorder. Therefore, if you have the condition and are planning to have children, it is recommended to seek genetic counselling and screening. This can provide information on the likelihood of your child having the disease or carrying the gene without showing symptoms. 

How common is Friedreich's ataxia?

Friedreich's ataxia is a relatively rare genetic disorder, affecting an estimated 1 in 50,000 people worldwide. The condition is more common in certain populations, particularly in those with European ancestry, and is less frequently reported in other parts of the world.

Is Friedreich's ataxia a terminal illness?

Friedreich's ataxia is a progressive and degenerative neurological disorder, and unfortunately, it can be terminal. Heart disease can become fatal by early adulthood and is the leading cause of death for people with Friedreich's ataxia. However, the course and severity of the disease can vary greatly between individuals, so some may experience a slower progression of symptoms and a longer lifespan. Treatment is available to manage symptoms and slow the disease progression, but currently, there is no known cure for Friedreich's ataxia.

When should I see a doctor?

If you are experiencing any symptoms that are characteristic of Friedreich's ataxia, such as difficulty with balance and coordination, muscle weakness, or decreased sensation in your arms and legs, it is essential to schedule an appointment with a doctor as soon as possible.

If you have a family history of Friedreich's ataxia, genetic testing can be performed to determine if you are at risk of developing the disorder, even if you have not experienced symptoms. It is important to discuss your concerns with a doctor, who can provide you with appropriate guidance and care.

Summary

Friedreich's ataxia is a genetic disorder caused by a mutation in the FXN gene, leading to a deficiency of frataxin, which regulates iron within cells. Symptoms include poor coordination, muscle weakness, sensory loss, slurred speech, cardiomyopathy, and diabetes. There is no cure for the condition, but treatments can help manage symptoms, and a healthy lifestyle can slow the progression of the disease.