Novel CLCN1 mutations in Taiwanese patients with myotonia congenita.
We have performed genetic screening on the skeletal muscle chloride channel gene (CLCN1) in Taiwanese population. A total of four patients with myotonia congenita (MC) together with 106 normal individuals were examined. All 23 exons of the CLCN1 gene were analysed by direct sequencing of PCR products to detect the nucleotide changes. Five mutations and three polymorphisms were identified in this study. Among these, three missense mutations (S471F, P575S, D644G) and one polymorphism (T736I) are novel and could be unique to the Taiwanese. In addition, a previously documented recessive G482R mutation was identified in a heterozygous patient and his nonsymptomatic father, indicating that this mutation might indeed function recessively or dominantly with incomplete penetrance. In conclusion, this is the first report of MC in Taiwan with proven CLCN1 gene mutations and showing high molecular heterogeneity in Taiwanese MC patients.
Department of Neurology, China Medical University Hospital, Taichung, Taiwan, Republic of China.
Shuo-Bin
SB
Jou
Ling-I
LI
Chang
Huichin
H
Pan
Pei-Ru
PR
Chen
Kuang-Ming
KM
Hsiao
D000293:Adolescent; D000328:Adult; D001224:Aspartic Acid / Q000235:genetics; D002648:Child; D018118:Chloride Channels / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000379:methods; D005260:Female; D005998:Glycine / Q000235:genetics; D006801:Humans; D007532:Isoleucine / Q000235:genetics; D008297:Male; D020125:Mutation, Missense; D009224:Myotonia Congenita / Q000235:genetics*; D010649:Phenylalanine / Q000235:genetics; D011110:Polymorphism, Genetic; D011392:Proline / Q000235:genetics; D012694:Serine / Q000235:genetics; D013624:Taiwan / Q000453:epidemiology; D013912:Threonine / Q000235:genetics
C086321:CLC-1 channel; D018118:Chloride Channels; D007532:Isoleucine; D013912:Threonine; D001224:Aspartic Acid; D012694:Serine; D010649:Phenylalanine; D011392:Proline; D005998:Glycine