Channelopathy

Channelopathy
Classification and external resources
Specialty
Patient UK	Channelopathy
MeSH	D053447

Channelopathies are diseases caused by disturbed function of ion channel subunits or the proteins that regulate them. These diseases may be either congenital (often resulting from a mutation or mutations in the encoding genes) or acquired (often resulting from autoimmune attack on an ion channel).

There are a large number of distinct dysfunctions known to be caused by ion channel mutations. The genes for the construction of ion channels are highly conserved amongst mammals and one condition, hyperkalemic periodic paralysis, was first identified in the descendants of Impressive, a registered Quarter Horse (see AQHA website).

The channelopathies of human skeletal muscle include hyper- and hypokalemic (high and low potassium blood concentrations) periodic paralysis, myotonia congenita and paramyotonia congenita.

Types

The types in the following table are commonly accepted. Channelopathies currently under research, like Kir4.1 potassium channel in multiple sclerosis, are not included.

Condition	Channel type
Alternating hemiplegia of childhood	Na⁺/K⁺-ATPase
Bartter syndrome	various by type
Brugada syndrome	various, by type
Catecholaminergic polymorphic ventricular tachycardia (CPVT)	Calcium channel
Congenital hyperinsulinism	Inward-rectifier potassium ion channel
Cystic fibrosis	Chloride channel
Dravet Syndrome	Voltage-gated sodium channel
Episodic Ataxia	Voltage-gated potassium channel
Erythromelalgia	Voltage-gated sodium channel
Generalized epilepsy with febrile seizures plus	Voltage-gated sodium channel
Familial hemiplegic migraine	various
Fibromyalgia	Voltage-gated sodium channel
Hyperkalemic periodic paralysis	Voltage-gated sodium channel
Hypokalemic periodic paralysis	Voltage-gated sodium channel or voltage-dependent calcium channel (calciumopathy)
Lambert-Eaton myasthenic syndrome	Voltage-gated calcium channel
Long QT syndrome main type Romano-Ward syndrome	various, by type
Malignant hyperthermia	Ligand-gated calcium channel
Mucolipidosis type IV	Non-selective cation channel
Myasthenia Gravis	Ligand-gated sodium channel
Myotonia congenita	Voltage-dependent chloride channel
Neuromyelitis optica	Aquaporin-4 water channel
Neuromyotonia	Voltage-gated potassium channel
Nonsyndromic deafness	various
Paramyotonia congenita (a periodic paralysis)	Voltage-gated sodium channel
Retinitis pigmentosa (some forms)	Ligand-gated non-specific ion channels
Short QT syndrome	various potassium channels suspected
Timothy syndrome	Voltage-dependent calcium channel
Tinnitus	Voltage-gated potassium channel of the KCNQ family
Seizure	Voltage-dependent potassium channel

External links

VIDEO Channel Surfing in Pediatrics by Carl E. Stafstrom, M.D., at the UW-Madison Health Sciences Learning Center.

• The Channelopathy Foundation - Foundation for Ion Channel diseases
• Cystic Fibrosis Foundation
• Rare Diseases Clinical Research Network