GMDS (GDP-mannose 4,6-dehydratase) catalyzes the conversion of GDP-D-mannose to GDP-4-dehydro-6-deoxy-D-mannose, a critical step in fucose biosynthesis 1. This enzyme functions primarily in GDP-L-fucose biosynthetic pathways and is involved in protein glycosylation, particularly fucosylation, which modulates cellular signaling including Notch pathway regulation. GMDS expression is significantly upregulated in lung adenocarcinoma, where it promotes cell proliferation and survival through mechanisms involving the CASP8-CDKN1A axis 2. GMDS knockdown impairs tumor cell growth and induces apoptosis both in vitro and in vivo 2. Beyond cancer, GMDS variants are associated with primary open-angle glaucoma susceptibility, with specific polymorphisms influencing intraocular pressure response to latanoprost treatment 34. Additionally, GMDS gene methylation increases dose-dependently in individuals chr6 exposed to arsenic, suggesting involvement in environmental carcinogenesis 5. The regulatory lncRNA GMDS-AS1 functions as an oncogenic factor, controlling cancer cell behaviors and inflammatory responses through miR-96-5p/caspase-2 signaling 16. GMDS represents a potential biomarker for cancer diagnosis and therapeutic target, with clinical significance for understanding fucosylation-dependent disease pathogenesis.