Features include always present findings: Absent speech, Severe global developmental delay, and Epileptic encephalopathy; and common findings: Bilateral tonic-clonic seizure, Focal impaired awareness seizure, Low muscle tone (hypotonia), and Nystagmus. 16 total HPO annotations.

GABRG2 encodes gamma-aminobutyric acid type A receptor subunit gamma2 (475 aa). Gamma subunit of the heteropentameric ligand-gated chloride channel gated by gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter in the brain. Highest expression in Brain Cerebellar Hemisphere (20.3 TPM) and Brain Frontal Cortex BA9 (19.4 TPM).

Developmental and epileptic encephalopathy, 74 is associated with mutations in the GABRG2 gene on chromosome 5.

GABRG2 is classified as a druggable target (Druggable Genome and Ion Channel categories) with score 0.4.

Genetic testing for GABRG2 is available. Testing is considered confirmatory for diagnosis.

Biomarker and diagnostic research for developmental and epileptic encephalopathy, 74 has been reported in the published literature.

Phenotype severity distribution: 3 always present features, 4 common features.

No clinical trials have been registered for developmental and epileptic encephalopathy, 74.

52 publications have been identified in PubMed for developmental and epileptic encephalopathy, 74. Research spans Epidemiology / Natural History (33%), Review / Meta-Analysis (23%), and Case Report / Case Series (14%).