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Identification and Classification of Position-specific GABAA Receptor Subunit Missense Variants for Their Role In Hippocampal Pyramidal Neurons
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Hyperekplexia: a Chinese adolescent with 2 novel mutations of the GLRA1 gene

Keung Kit Chan1, Sharon Wan-Wah Cherk, Hencher Han-Chih Lee

  • 11Private Practice, Hong Kong.

Journal of Child Neurology
|November 13, 2012
PubMed

Insights

Hyperekplexia, a rare neurologic disorder causing excessive startle responses, can be misdiagnosed as epilepsy. Early diagnosis and treatment with clonazepam significantly improve patient quality of life.

Area of Science:

  • Neurology
  • Genetics

Background:

  • Hyperekplexia is a rare genetic disorder characterized by an exaggerated startle reflex.
  • Key features include neonatal generalized stiffness, hyperreflexia, and brief motor inhibition post-startle.

Observation:

  • A patient presented with frequent falls due to stimuli, initially misdiagnosed as epilepsy.
  • Clinical symptoms included excessive startle responses to auditory and tactile stimuli.

Findings:

  • Genetic analysis revealed novel mutations in the GLRA1 gene: c.497G>C (p.Cys166Ser) and c.526delG (p.Asp176Metfs*16).
  • These mutations are associated with the hyperekplexia phenotype.

Implications:

  • Accurate diagnosis of hyperekplexia is crucial to avoid misdiagnosis, such as epilepsy.
  • Clonazepam demonstrated dramatic efficacy, enabling the patient to participate in sports and social activities.
  • Identifying novel GLRA1 mutations expands the genetic understanding of hyperekplexia.

Keywords:
GLRA1 geneclonazepamexcessive startle responsehead retraction reflexhyperekplexianeurogenetic

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