Novel CLCN1 Mutations and Clinical Features of Korean Patients with Myotonia Congenita.
10.3346/jkms.2009.24.6.1038
- Author:
In Soo MOON
1
;
Hyang Sook KIM
;
Jin Hong SHIN
;
Yeong Eun PARK
;
Kyu Hyun PARK
;
Yong Bum SHIN
;
Jong Seok BAE
;
Young Chul CHOI
;
Dae Seong KIM
Author Information
1. Department of Neurology, Dae-Dong Hospital, Busan, Korea.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
Myotonia Congenita;
CLCN1;
Clinical Features
- MeSH:
Adult;
Amino Acid Sequence;
Asian Continental Ancestry Group/*genetics;
Base Sequence;
Child, Preschool;
Chloride Channels/*genetics;
DNA Mutational Analysis;
Exons;
Humans;
Infant;
Korea;
Male;
Molecular Sequence Data;
Myotonia Congenita/*genetics;
*Point Mutation;
Protein Conformation;
Young Adult
- From:Journal of Korean Medical Science
2009;24(6):1038-1044
- CountryRepublic of Korea
- Language:English
-
Abstract:
Myotonia congenita (MC) is a form of nondystrophic myotonia caused by a mutation of CLCN1, which encodes human skeletal muscle chloride channel (CLC-1). We performed sequence analysis of all coding regions of CLCN1 in patients clinically diagnosed with MC, and identified 10 unrelated Korean patients harboring mutations. Detailed clinical analysis was performed in these patients to identify their clinical characteristics in relation to their genotypes. The CLCN1 mutational analyses revealed nine different point mutations. Of these, six (p.M128I, p.S189C, p.M373L, p.P480S, p.G523D, and p.M609K) were novel and could be unique among Koreans. While some features including predominant lower extremity involvement and normal to slightly elevated creatine kinase levels were consistently observed, general clinical features were highly variable in terms of age of onset, clinical severity, aggravating factors, and response to treatment. Our study is the first systematic study of MC in Korea, and shows its expanding clinical and genetic spectrums.
