MOXD1 (monooxygenase DBH-like 1) is an endoplasmic reticulum membrane-bound oxidoreductase with emerging roles in development and disease. It possesses oxidoreductase activity acting on paired donors with incorporation of molecular oxygen and reduced ascorbate 1. Functionally, MOXD1 is a lineage-restricted tumor suppressor gene in neuroblastoma, with expression highly conserved in mesenchymal neuroblastoma cells and Schwann cell precursors during healthy development 2. Loss of MOXD1 expression associates with advanced neuroblastoma and worse patient outcomes 2. Conversely, MOXD1 is upregulated in multiple cancer contexts: it promotes gastric cancer malignancy through FTO-mediated m6A methylation regulation 3, and is upregulated in high-grade serous ovarian cancer metastatic tumors 4. Beyond oncology, elevated hepatic MOXD1 expression occurs in alcoholic liver disease, and fenofibrate reduces disease severity by downregulating MOXD1 expression 1. MOXD1 also serves as a putative biomarker in mitochondrial disease diagnosis 5 and is among genes associated with silicosis through cuproptosis-related mechanisms 6. A p.(Trp276Gly) variant in MOXD1 cosegregates with autosomal dominant sleep-related hypermotor epilepsy, suggesting neurological roles 7. Additionally, MOXD1 is upregulated in both chr6 obstructive pulmonary disease and heart failure as a co-susceptibility gene 8.