EIF2B5 encodes the epsilon subunit of the eukaryotic translation initiation factor 2B (eIF2B) complex, serving as a critical guanine nucleotide exchange factor 1. Its primary function is to catalyze GDP-GTP exchange on eIF2 gamma subunits, facilitating protein translation initiation 123. When eIF2 alpha is phosphorylated during cellular stress, EIF2B5 activity is repressed, suppressing global translation and limiting methionyl-initiator tRNA availability 13. EIF2B5 mutations cause leukoencephalopathy with vanishing white matter (VWM), a progressive hereditary white matter disorder characterized by ataxia, spasticity, and neurological degeneration 45. VWM presents with distinctive episodes of rapid deterioration triggered by infections, seizures, or trauma 5. Astrocytic dysfunction is central to VWM pathophysiology 5. EIF2B5 is the most frequently mutated gene among EIF2B family members 6. Preliminary evidence suggests potential overlap between EIF2B5 mutations and multiple sclerosis susceptibility, though this relationship remains contentious 7. Clinically, therapeutic approaches targeting EIF2B5 show promise: astrocyte-targeted AAV9-mediated EIF2B5 gene supplementation demonstrated safety and early efficacy in mouse models, with improvements in motor function, body weight, and demyelination attenuation 5. Adenine base editing approaches achieved partial integrated stress response recovery 8.