Novel CACNA1S Mutation c.3491 A>C in Hypokalemic Periodic Paralysis: First Report with Functional Validation.

Area of Science:

• Genetics
• Molecular Biology
• Neurology

Background:

• Hypokalemic periodic paralysis (HypoPP) is a muscle channelopathy.
• Characterized by recurrent paralysis and hypokalemia.
• Triggers include cold, exercise, diet, and overeating.

Purpose of the Study:

• Elucidate the pathogenic mechanism of novel CACNA1S gene mutations in HypoPP.
• Investigate a specific mutation (p. Glu1164Ala) in a patient.
• Identify potential new pathogenic pathways for HypoPP.

Main Methods:

• Whole-exome sequencing (WES) for genetic analysis.
• American College of Medical Genetics and Genomics (ACMG) compliance analysis.
• Serum potassium, blood biochemistry, and protein structure prediction.

Main Results:

• Identified a novel CACNA1S gene mutation (NM_000069.3: exon27: c.3491 A>C [p. Glu1164Ala]) in a patient with HypoPP.
• The mutation, initially classified as uncertain, was confirmed as pathogenic.
• The mutation induced a conformational change in the calcium ion channel, explaining the disease mechanism.

Conclusions:

• Reported a new mutation site in the CACNA1S gene associated with HypoPP.
• Proposed a novel pathogenic mechanism involving calcium ion channel dysfunction.
• Highlighted obesity and low magnesium as potential risk factors and triggers for HypoPP.