The novel hyperekplexia allele GLRA1(S267N) affects the ethanol site of the glycine receptor.

Mutations in the GLRA1 gene, which encodes the alpha1-subunit of the inhibitory glycine receptor (GlyR), are the underlying causes in the majority of cases of hereditary startle disease (OMIM no. 149400). GlyRs are modulated by alcohols and volatile anesthetics, where a specific amino acid at position 267 has been implicated in receptor modulation.