title: Identification of a novel missense GLRA1 gene mutation in hyperekplexia: a case report.
abstract: BACKGROUND
  Hereditary hyperekplexia is a neurological disorder characterized by excessive startle responses with violent jerking to noise or touch, stiffening of the trunk and limbs, clenching of the fists and attacks of a high-frequency trembling. Hyperekplexia has a heterogeneous genetic background with several identified causative genes and demonstrates both dominant and recessive inheritance. Mutations in the glycine receptor alpha 1 subunit gene occur in about 30 percent of hyperekplexia cases.
  
  
  METHODS
  In this study, we report the case of a Hungarian boy whose abnormal movements, muscle stiffness and convulsions were first noted when he was 4 days old. Neurological and electrophysiological investigation suggested the clinical diagnosis of hyperekplexia.
  
  
  CONCLUSIONS
  Direct sequencing of the coding regions and the flanking introns of the glycine receptor alpha 1 subunit gene revealed a novel heterozygous missense mutation (c.211A/T, p.Ile71Phe). Genetic screening of our patient's family revealed that the clinically unaffected parents and sister do not carry the mutation, suggesting that the identified sequence change is a de novo mutation. Since hyperekplexia can have severe consequences, including sudden infant death due to laryngospasm and cardiorespiratory failure, identification of the causative genetic alteration(s) of the disease is high priority. Such knowledge is necessary for prenatal diagnosis, which would allow informed family planning and greater parental sensitivity to hyperekplexia 1-associated risks.
authors: Emese
authors: E
authors: Horváth
authors: Katalin
authors: K
authors: Farkas
authors: Agnes
authors: A
authors: Herczegfalvi
authors: Department of Medical Genetics, University of Szeged, Somogyi utca 4, H-6720 Szeged, Hungary. nikoletta.nagy@gmail.com.
authors: Nikoletta
authors: N
authors: Nagy
authors: Márta
authors: M
authors: Széll
mesh_terms: D006801:Humans; D007231:Infant, Newborn; D008297:Male; D020125:Mutation, Missense; D018009:Receptors, Glycine / Q000235:genetics*; D016750:Stiff-Person Syndrome / Q000235:genetics*
chemical_list: C000657604:GLRA1 protein, human; D018009:Receptors, Glycine