A Mutation in the KCNE3 Potassium Channel Gene Is Associated with Susceptibility to Thyrotoxic Hypokalemic Periodic Paralysis

• DOI: 10.1210/jc.2002-020698
• Publication Date: 2002-11-02T03:22:01Z
• Authors: Magnus R. Dias Da...; Janete M. Cerutti; Liliane A. T. Arn...; Rui M. B. Maciel
• Keywords: Hypokalemic periodic paralysis; Periodic paralysis; Thyrotoxic periodic paralysis

Abstract Hypokalemic Periodic Paralyses comprise diverse diseases characterized by acute and reversible attacks of severe muscle weakness, associated with low serum potassium. The most common causes are Familial Paralysis (FHypoKPP), an autosomal dominant disease, Thyrotoxic (THypoKPP), secondary to thyrotoxicosis. Symptoms paralysis similar in both diseases, distinguished thyrotoxicosis present THypoKPP. FHypoKPP is caused mutations ionic channel genes calcium (CACN1AS), sodium (SCN4A) potassium (KCNE3). Since similar, we tested the hypothesis that THypoKPP could carry same described FHypoKPP, being a genetically conditioned complication In 15 patients THypoKPP, using target-exon PCR, CSGE screening, direct sequencing, excluded known CACN1AS SCN4A genes. On other hand, were able identify R83H mutation KCNE3 gene one sporadic case man who had been asymptomatic until developing Graves’ disease; confirmed disease-causing 2 3 descendants. was recently found two unrelated families, which mutant decreased outward flux, resulting more positive resting membrane potential. We, therefore, identified first genetic defect gene.