B3GAT2 (beta-1,3-glucuronyltransferase 2) is a Golgi membrane-localized enzyme that catalyzes the biosynthesis of the L2/HNK-1 carbohydrate epitope on both glycolipids and glycoproteins 1. This carbohydrate modification is particularly important in the nervous system, where it is expressed on cell adhesion molecules and plays roles in synaptic plasticity and memory formation 1. B3GAT2 has emerged as a disease-relevant gene across multiple conditions. Genetic variants in B3GAT2 are associated with schizophrenia susceptibility, with risk alleles correlating with decreased cortical surface area 2. The gene has also been implicated in pediatric venous thromboembolism through genome-wide association studies, suggesting a role in vascular biology 3. Beyond genetic associations, B3GAT2 shows clinical utility as a cerebrospinal fluid biomarker for predicting shunt responsiveness in idiopathic normal pressure hydrocephalus patients 4. Aberrantly methylated B3GAT2 has been identified as a potential biomarker for Barrett's esophagus, a preneoplastic condition preceding esophageal adenocarcinoma 5. Additionally, B3GAT2 appears in metabolism-related gene signatures predictive of prognosis in both Wilms tumor and prostate cancer 67, and shows differential methylation in plasma cell-free DNA of lung cancer patients 8, suggesting broader oncological relevance.