CLN8 is a transmembrane endoplasmic reticulum and ERGIC protein that functions as a lysophosphatidylglycerol acyltransferase catalyzing essential steps in bis(monoacylglycero)phosphate biosynthesis, a phospholipid critical for lysosome function 1. CLN8 belongs to the TRAM-LAG1-CLN8 domain protein family involved in phospholipid remodeling and membrane homeostasis 1. The protein is developmentally regulated in the CNS, with highest expression in cortex and hippocampus, suggesting roles in neuronal maturation and survival 2. CLN8 is involved in trafficking of lysosomal enzymes and regulation of cellular phospholipid composition 3. Biallelic mutations in CLN8 cause neuronal ceroid lipofuscinosis (Batten disease), the most common childhood neurodegenerative disease, characterized by progressive seizures, cognitive decline, motor dysfunction, visual loss, and intraneuronal accumulation of autofluorescent lipid-protein deposits 45. Clinical phenotype varies from mild progressive epilepsy with mental retardation (Northern epilepsy/EPMR) to severe late infantile variants 46. A single neonatal intracerebroventricular AAV9 gene therapy delivery in CLN8-disease mice restored lifespan from 10 months to beyond 24 months, reducing pathological hallmarks and behavioral abnormalities 3, supporting therapeutic development for this currently incurable disorder.