PEDS1 (plasmanylethanolamine desaturase 1) is a transmembrane enzyme located in the endoplasmic reticulum that catalyzes the final step of plasmalogen biosynthesis by introducing a vinyl ether double bond into plasmanylethanolamine phospholipids 1. Plasmalogens are specialized glycerophospholipids with unique antioxidative properties and roles in membrane organization and signaling 2. The enzyme contains eight conserved histidines essential for activity and requires a critical aspartate residue (Asp100) for function 1. PEDS1 deficiency causes striking metabolic consequences, including massive accumulation of plasmanyl lipids and severe reduction of plasmenyl lipids across tissues 3. Clinically, PEDS1 mutations are associated with neurodevelopmental disorders, including microcephaly, global developmental delay, and congenital cataracts 4. In mouse models, Peds1 knockout results in growth phenotypes, accelerated neuronal cell-cycle exit, and impaired neuronal differentiation and migration 4. The enzyme also regulates ether lipid homeostasis in adipocytes and correlates with circulating lipid profiles 5. Additionally, PEDS1 genetic variants are associated with Long COVID susceptibility 6, and the gene plays a role in cancer cell resistance to oxidative stress through lipid peroxidation protection 7.