Based on the review of all previously reported CLCN1-related MC patients in China, autosomal dominant Thomsen's disease compromised 48.3% of the patients, which was much higher than the percentage of 19–20% in one study (32), but lower than another report from Japan, which enrolled 30 families with myotonia congenita and showed that the dominant form consisted of 67% (27). This evidence concerns the gene CLCN1 and Thomsen and Becker disease.