Hyperkalemic periodic paralysis and paramyotonia congenita – A novel sodium channel mutation –

  title={Hyperkalemic periodic paralysis and paramyotonia congenita – A novel sodium channel mutation –},
  author={Shiho Okuda and Fumio Kanda and Keisuke Nishimoto and Ryogen Sasaki and Kazuo Chihara},
  journal={Journal of Neurology},
Sirs: The group of hereditary sodium channel diseases, also termed sodium channelopathies, comprises hyperkalemic periodic paralysis (HyperPP), some forms of hypokalemic periodic paralysis, paramyotonia congenita (PC) and potassium aggravated myotonia [1, 4, 5, 7, 8]. They occur by autosomal dominant inheritance caused by point mutations in the gene encoding the α-subunit of the adult human skeletal muscle sodium channel (SCN4A) [1, 7, 8]. Here we report a case of HyperPP and PC with novel… 

New mutations of SCN4A cause a potassium-sensitive normokalemic periodic paralysis

A potassium-sensitive and normokalemic type of periodic paralysis caused by new SCN4A mutations at codon 675 is reported.

[Hyperkalemic periodic paralysis: a Spanish family with the p.Thr704Met mutation in the SCN4A gene].

The findings of the studied family correlate well with those reported previously in HYPP, although the frequency of the episodes is exceptionally high in the family.

Periodic paralysis.

Paramyotonia Congenita with Persistent Distal and Facial Muscle Weakness: A Case Report with Literature Review.

PC associated with the T1313M mutation is a possible cause of persistent distal hand weakness and Phenotypic variation within the family was remarkable, as the two younger affected patients did not present with persistent weakness or muscle atrophy.

N1366S mutation of human skeletal muscle sodium channel causes paramyotonia congenita

It is demonstrated that N1366S is a disease‐causing mutation and that the temperature‐sensitive alteration of N1365S channel activity may be responsible for the pronounced paramyotonia congenita symptoms of these patients.

Paralysis periodica paramyotonica caused by SCN4A Arg1448Cys mutation.

Thr1313Met mutation in skeletal muscle sodium channels in a Japanese family with paramyotonia congenita.

A 37-year-old Japanese woman was referred from another clinic to confirm the diagnosis of myotonia congenita, the prevalence of which is very low in Japan, was diagnosed based on their clinical features and DNA analysis results.

[Hyperkalemic periodic paralysis].

Muscle strength usually returns to normal between attacks, although many affected people continue to experience mild stiffness (myotonia), particularly in muscles of the face and hands.

A genetic investigation of the muscle and neuronal channelopathies: from Sanger to next-generation sequencing

Next-generation sequencing proved to be a more thorough and efficient method for channelopathy genetic diagnosis and several novel findings throughout the thesis expanded the current knowledge within the field.



A novel sodium channel mutation causing a hyperkalemic paralytic and paramyotonic syndrome with variable clinical expressivity

The results are remarkable with respect to the lack of complete penetrance usually seen with sodium channelopathies and the site of mutation that was formerly not thought to be involved in channel inactivation.

Voltage-sensor sodium channel mutations cause hypokalemic periodic paralysis type 2 by enhanced inactivation and reduced current.

The results prove that SCN4A, the gene encoding the sodium channel alpha subunit of skeletal muscle is responsible for HypoPP-2, a disease caused by enhanced channel inactivation and current reduction showing no myotonia.

Mutant channels contribute <50% to Na+ current in paramyotonia congenita muscle.

Comparing the gating defects of two human muscle Na+ channel mutants causing paramyotonia congenita in native muscle specimens from two patients with those of the same mutant recombinant channels expressed in human embryonic kidney cells raises the possibility that variability in the ratio of mutant to wild-type Na+ channels in the muscle membrane has an impact on the clinical severity of the phenotype.

Voltage-gated ion channels and hereditary disease.

Unique among reviews of this topic is that all known human hereditary diseases of voltage-gated ion channels are described covering various fields of medicine such as neurology, nephrology, and cardiology, with interesting parallels in mechanisms of disease emphasized.

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edited by Allan H. Ropper and Martin A. Samuels , 1572 pp., McGraw Hill Medical, 2009, $159 Upon receiving the request to review the ninth edition of Adams and Victor's Principles of Neurology , I

Ion Channels And Disease

This chapter considers what is known of ion channel structure, explains the properties of the single ion channel, and shows how single-channel currents give rise to action potentials and synaptic potentials.

The hereditary myotonias and periodic paralysis

  • 2001