Identification of a de novo Lys304Gln mutation in the glycine receptor alpha-1 subunit gene in a Korean infant with hyperekplexia.
Startle disease or hyperekplexia (STHE; MIM 149400) is a rare disorder that is characterized by marked muscular hypertonia in infancy and an exaggerated startle response to unexpected acoustic or tactile stimuli. Mutations in the gene encoding the alpha-1 subunit of the inhibitory glycine receptor (GLRA1) were reported as causes of STHE. Recently, we encountered a Korean male infant with generalized stiffness that was observed from the first 3 days of life. The abnormal startle response was evident from the fourth week of life, and he showed marked improvement in the startle response and muscle hypertonia after being administered phenobarbital and clonazepam. Direct sequencing analysis of the infant and his parents revealed a de novo variation (c.910A>C) in the GLRA1 gene, resulting in a novel Lys304Gln missense mutation.
Kang
Hoon-Chul
HC
Department of Pediatrics, Epilepsy Center, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Korea.
Jeong You
Su
S
Jae Chey
Myung
M
Sam Baik
Jong
J
Kim
Jong-Won
JW
Ki
Chang-Seok
CS
D044466:Asian People / Q000235:genetics*; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D005091:Exons / Q000235:genetics; D015870:Gene Expression / Q000235:genetics*; D023281:Genomics / Q000379:methods; D006801:Humans; D007223:Infant; D007438:Introns / Q000235:genetics; D008297:Male; D017354:Point Mutation / Q000235:genetics*; D018009:Receptors, Glycine / Q000235:genetics*; D013216:Reflex, Startle / Q000235:genetics*; D017422:Sequence Analysis, DNA
D017931:DNA Primers; D018076:DNA, Complementary; C000657604:GLRA1 protein, human; D018009:Receptors, Glycine