Familial Hypokalemic Periodic Paralysis is classified as a channelopathy.
Courtesy of WiseGeek.com:
"Channelopathies are diseases of the ion channels, structures allowing for the passage of ions across the membranes of individual cells. These conditions can also involve the regulatory proteins responsible for moderating the behavior of ion channels. In both cases, the channels do not function properly, causing disease in the patient. The nature of the disease can vary considerably with hundreds of different kinds of ion channels in the body, and treatment options are dependent on the channels involved and how the channelopathy manifests.
There are two types of channelopathies: congenital and acquired. Congenital conditions are genetic in nature and can be inherited or the result of spontaneous mutations. Acquired conditions, most commonly associated with autoimmune disease, occur later in life when the body begins attacking its own ion channels, incorrectly identifying them as foreign proteins. Channelopathies can cause both neurological and muscular disorders depending on the nature of the disease and the channels involved.
Migraines, some forms of epilepsy, cystic fibrosis, and myasthenia gravis, among many other conditions, can be associated with channelopathies. Typically, the patient experiences attacks in the form of paroxysms leading to temporary paralysis or other impairments. These attacks can grow more severe over time as the ion channels experience increasing levels of damage and become more dysfunctional. Patients may need mobility aids and other forms of support, along with medications to manage some symptoms.
Study into channelopathies is a complex and rich field of research in the sciences, especially since many animals develop similar conditions across species. Researchers are interested in identifying the origins and potential treatments of known channelopathies with the goal of assisting people who have these conditions. It is usually not possible to effect a cure, but patients may be able to manage the disease and its symptoms with medical support, and this can make it easier to live with a channelopathy, extending a patient's lifespan and keeping people more comfortable.
In families with a history of channelopathy, it can be advisable to discuss the situation with a genetic counselor before having children. The counselor can provide information about the likelihood of passing the conditions on to children and can also provide information about management of channelopathies to help people prepare in the event that they have children with diseases involving the ion channels. Genetic counseling can also be an opportunity to discuss other concerns with family history, such as histories of cancer and certain kinds of mental illness."
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