GABRA2 encodes the alpha-2 subunit of GABA(A) receptors, which are ligand-gated chloride channels that mediate fast synaptic inhibition in the brain 1. When activated by GABA, the major inhibitory neurotransmitter, these heteropentameric receptors allow chloride influx into neurons, hyperpolarizing the membrane and reducing action potential generation 1. The alpha-2 subunit exhibits synaptogenic activity with beta-2 subunits, contributing to synaptic contact formation. GABRA2 undergoes complex alternative splicing and promoter usage, generating multiple isoforms with naturally occurring haplotypes exhibiting different promoter activities, suggesting regulatory variation affects gene expression 2. Mutations in GABRA2 are associated with developmental and epileptic encephalopathy 78, as genetic variations in GABA receptor genes lead to epilepsy primarily through downregulating receptor expression and reducing GABA-evoked potentials 3. Beyond epilepsy, GABRA2 variants show robust associations with alcohol use disorder, with specific single-nucleotide polymorphisms (rs567926, rs279858) demonstrating significant risk across multiple meta-analyses 4. Evidence indicates gene-environment interactions, where GABRA2 risk genotypes interact with marital status and trauma exposure to influence alcohol dependence and posttraumatic stress disorder development 56. These findings establish GABRA2 as a critical neurobiological candidate gene affecting multiple neuropsychiatric phenotypes through GABAergic regulation.