What is inherited neuropathy? 

Inherited neuropathy refers to a group of genetic conditions where damage to the peripheral nerves is caused by an inherited fault in the DNA. Unlike acquired neuropathies, which are caused by external factors like diabetes or toxins, inherited neuropathies are present from birth, although symptoms may not appear until childhood, adolescence, or even adulthood. In the United Kingdom, these conditions affect approximately 1 in 2,500 people, with Charcot Marie Tooth disease being the most common form. 

Because these conditions are rooted in the genetic code, they are typically progressive, meaning the symptoms slowly worsen over time. They are often classified based on which part of the nerve is affected: the axon, which is the central cable, or the myelin sheath, which is the protective insulation. This article explores the common types of inherited neuropathy, the specific physical signs to look for, and the diagnostic process within the UK healthcare system. 

What We Will Discuss In This Article 

• Charcot Marie Tooth disease: The primary inherited neuropathy 

• Hereditary Neuropathy with liability to Pressure Palsies 

• Physical symptoms: Foot deformities and muscle wasting 

• Genetics and inheritance patterns like Autosomal Dominant versus Recessive 

• The NHS diagnostic pathway: Genetic testing and nerve conduction studies 

• Emergency guidance for acute complications or injury risk 

Common Types of Inherited Neuropathy 

While there are many rare variants, two main conditions account for the majority of cases seen in UK clinics. 

Charcot Marie Tooth (CMT) Disease 

CMT is a group of disorders that cause progressive muscle weakness and sensory loss. It is often divided into two main types: 

• CMT Type 1: Primarily affects the myelin sheath, known as demyelinating, leading to slow nerve signals. 

• CMT Type 2: Primarily affects the axon itself, reducing the strength of the signal. 

Hereditary Neuropathy with liability to Pressure Palsies (HNPP) 

HNPP is a condition where nerves are hypersensitive to physical pressure. Even minor pressure that would normally cause a limb to go to sleep can lead to prolonged periods of numbness or weakness that last for weeks or months. 

Physical Symptoms and Presentation 

Inherited neuropathies often follow a very specific physical pattern. Because the longest nerves are affected most severely, the symptoms typically begin in the feet and ankles before progressing to the hands. 

• Foot Deformities: Many patients develop very high arches, known as pes cavus, or hammer toes. Some may have very flat feet. 

• Champagne Bottle Legs: As the muscles in the lower leg waste away, a process called atrophy, the legs can take on the appearance of an inverted champagne bottle. 

• Gait and Balance: Weakness in the ankle muscles often causes foot drop, leading to an awkward walking style and frequent tripping or falls. 

• Hand Weakness: In later stages, fine motor tasks like buttoning a shirt or writing can become difficult. 

• Sensory Loss: Numbness or tingling in the hands and feet is common, though pain is usually a secondary symptom caused by joint strain rather than the nerve damage itself. 

Genetics and Inheritance 

Inherited neuropathies are caused by mutations in genes responsible for nerve structure or function. In the UK, the most common mutation is a duplication of the PMP22 gene. 

• Autosomal Dominant: The most common pattern, where a child has a 50 percent chance of inheriting the condition from just one affected parent. 

• Autosomal Recessive: Rarer forms where a child must inherit a faulty gene from both parents. 

• X linked: The gene is carried on the X chromosome, often affecting males more severely than females. 

The NHS Diagnostic Pathway 

If you or your GP suspect an inherited neuropathy, you will usually be referred to a neurologist. The diagnostic process in the UK typically includes: 

1. Physical Examination: Checking for high arches, muscle wasting, and loss of reflexes. 

2. Nerve Conduction Studies: Using small electrical shocks to measure how fast and strong signals move through your nerves. 

3. Genetic Testing: A blood test to look for specific gene mutations like the PMP22 duplication. 

4. Genomic Counselling: Specialist advice to help you understand the risks for future children and the implications for your wider family. 

Emergency Guidance 

Inherited neuropathies are generally slow moving, but they can create risks that require urgent care. Seek medical attention immediately if you experience: 

• A sudden, severe loss of muscle strength that makes walking or breathing difficult 

• Signs of a severe foot infection or ulcer that you did not feel due to numbness 

• An acute injury or fracture resulting from a fall caused by loss of balance 

• New, severe weakness in a single limb following minor pressure, which is common in HNPP 

• Sudden difficulty swallowing or a rapid change in your voice 

In these situations, call 999 or attend your nearest Accident and Emergency department immediately. 

To Summarise 

Inherited neuropathy is a life long genetic condition that primarily impacts the strength and sensation of the limbs. In the UK, conditions like Charcot Marie Tooth disease are managed through a combination of physiotherapy, orthotics such as splints, and regular monitoring. While there is currently no cure, early diagnosis is essential for preventing secondary injuries and managing symptoms effectively. Understanding the genetic nature of the condition also allows for better family planning and ensures that patients receive the specialized support they need to maintain their independence. 

Authority Snapshot 

This article was reviewed by Dr. Rebecca Fernandez, a UK trained physician with an MBBS and extensive experience in internal medicine, surgery, and emergency care. Dr. Fernandez has managed critically ill patients and stabilized acute trauma cases, giving her a deep understanding of the physical and systemic complications of nerve damage. Her background in evidence based psychiatry and digital health ensures a holistic perspective on managing the long term physical and mental health challenges associated with progressive inherited conditions.