Investigation of Human Neurological Ion Channel Disorders

In the walls of brain, nerve and muscle cells are small pores, called ion channels which allow ions (charged particles) to move in and out of the cell.  These channels are important for the electrical signals that the brain, muscles and nerves need to function.

Problems with their normal function can arise when there are changes in the genetic code for ion channels, or other genes that interact or affect ion channels. 

These ion channels are usually specific for a particular ion e.g. potassium or calcium. Depending on the specific ion channel affected the features of these conditions can include:

• muscle weakness
• muscle stiffness
• muscle twitching (myotonia or neuromyotonia)
• episodic ataxia
• episodic weakness in disorders such as myasthenia gravis
• epilepsy or episodes of altered consciousness
• migraine or rare headache disorders such as cluster headache and episodic pain
• unusual sleep pattern or altered consciousness such as Kleine-Levin syndrome
• sleep disorders such as parasomnias
• episodes of unsteadiness with walking

This covers a range of conditions of the muscle, spinal cord and brain. There is evidence that genetic changes in ion channels play a role in these disorders.

Research is underway to identify genetic factors in epilepsy and other neurological diseases.

Study information

Patients in this study will be asked about their medical history and undergo clinical assessment and some tests.  Patients may be asked not to take their prescribed medication for a day as the drugs can affect the test results. The tests may include:

• Videoing of the neurological examination, such as the way someone walks, their eye movements or speech.  
• Electrocardiogram (ECG) looking at the electrical functioning of the heart. 
• Nerve excitability tests where electrical pulses are applied to the wrist and the muscle response recorded at the base of the thumb
• Blood sample for genetic analysis. 
• Urine or hair sample for biochemical analysis.

If patients have already had skin or muscle biopsies* we will ask their permission to use tissue from biopsies for more tests.

Primary objective

To improve our understanding of the clinical and genetic features of channelopathies. This will allow us to work out better ways to diagnose and treat these conditions in the future.

New mutations will be studies in the laboratory to find out how these genetic changes result in faulty ion channels. 

* the removal of small amounts of tissue for testing