The genotype and clinical phenotype of Korean patients with familial hypokalemic periodic paralysis.
Familial hypokalemic periodic paralysis (HOPP) is a rare autosomal-dominant disease characterized by reversible attacks of muscle weakness occurring with episodic hypokalemia. Mutations in the skeletal muscle calcium (CACNA1S) and sodium channel (SCN4A) genes have been reported to be responsible for familial HOPP. Fifty-one HOPP patients from 20 Korean families were studied to determine the relative frequency of the known mutations and to specify the clinical features associated with the identified mutations. DNA analysis identified known mutations in 12 families: 9 (75%) were linked to the CACNA1S gene and 3 (25%) to the SCN4A gene. The Arg528His mutation in the CACNA1S gene was found to be predominant in these 12 families. Additionally, we have detected one novel silent exonic mutation (1950C>T) in the SCN4A gene. As for a SCN4A Arg669His mutation, incomplete penetrance in a woman was observed. Characteristic clinical features were observed both in patients with and without mutations. This study presents comprehensive data on the genotype and phenotype of Korean families with HOPP.
Kim
June Bum
JB
Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Kim
Man Ho
MH
Lee
Soon Ju
SJ
Kim
Dae Joong
DJ
Lee
Byung Churl
BC
D000293:Adolescent; D000328:Adult; D015220:Calcium Channels / Q000235:genetics*; D020746:Calcium Channels, L-Type; D002648:Child; D002675:Child, Preschool; D005838:Genotype; D006801:Humans; D020514:Hypokalemic Periodic Paralysis / Q000235:genetics*; D007223:Infant; D009154:Mutation; D062553:NAV1.4 Voltage-Gated Sodium Channel; D010641:Phenotype; D015222:Sodium Channels / Q000235:genetics*
C412223:CACNA1S protein, human; D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D062553:NAV1.4 Voltage-Gated Sodium Channel; C106251:SCN4A protein, human; D015222:Sodium Channels