hereditary hyperekplexia (Kok disease, startle disease, stiff baby syndrome)

Genetics

• associated with mutations in glycine receptor alpha-1 gene
• associated with mutations in glycine receptor beta gene
• hypereplexia with epilepsy associated with mutations in the ARHGEF9 gene
• associated with defects in GPHN
• associated with defects in SLC6A5
• autosomal dominant or autosomal recessive

Clinical manifestations

• abnormal startle reflex
• muscle hypertonia
• myoclonus
• +/- epilepsy

More general terms

• developmental disorder
• genetic disease of the central nervous system

Database

• OMIM: https://mirror.omim.org/entry/149400
• OMIM: https://mirror.omim.org/entry/138491