Mutation status of gene CACNA1S and SCN4A in the hypokalemic periodic paralysis pedigree in Chinese population / 解放军医学杂志

ABSTRACT

Objective To investigate the mutation status of gene CACNA1S and SCN4A in hypokalemic periodic paralysis (HPP) pedigree of Chinese population, and compare the status with that in Caucasian populations as reported in previous literature. Methods To define the gene mutation status, the genes CACNA1S and SCN4A were sequenced by PCR and DNA sequencing technology in two familial HPP pedigrees, one hyperthyroid HPP pedigree and four sporadic HPP patients, the findings were then compared with the reference sequences in gene library. A total of nine relevant reports concerning the gene CACNA1S and SCN4A mutation of HPP pedigree published from Jan. 1999 to Dec. 2012 were retrieved from PubMed database. Results All the probands were suffering from paroxysmal muscle weakness with hypokalemia. As a typical symptom of HPP, muscle weakness often involved the extremities. Auxiliary examination confirmed serum hypopotassemia, electrocardiogram (ECG) showed hypokalemic change, and electromyography (EMG) showed shortened motor potential duration and low amplitude. All the findings mentioned above were in accordance with clinical diagnosis of HPP. Gene analysis indicated that no mutation of CACNA1S and SCN4A was found in the probands, the family members of the three HPP pedigrees and the four patients of sporadic HPP. The previous literature presented that mutation rate of gene CACN1AS and SCN4A was much higher in Caucasian HPP patients than in Chinese population. Conclusion The mutation rate of gene CACN1AS and SCN4A is lower in Chinese HPP patients than in Caucasian patients with significant difference.