ADH1A (alcohol dehydrogenase 1A) is a cytosolic NAD+-dependent enzyme that oxidizes primary and secondary alcohols and catalyzes retinol metabolism 1. The gene is regulated by transcription factors GATA-2 and HNF-3β, which bind distal cis-acting elements to control tissue-specific expression in hepatocytes 2. Functionally, ADH1A metabolizes ethanol, with genetic variants (rs1229976) significantly affecting blood acetaldehyde concentrations after alcohol intake 3. Beyond alcohol metabolism, ADH1A emerges as a multifunctional biomarker in disease contexts: it is downregulated in HBV-related hepatocellular carcinoma and associated with metabolic reprogramming 4, upregulated in alcoholic liver disease models alongside ethanol metabolism and inflammation 5, and identified as a potential prognostic marker in breast cancer where its suppression increases migratory and invasive capacity 6. ADH1A is also significantly elevated in childhood central obesity and associated with lipid metabolism dysregulation 7. ADH1A variants correlate with substance dependence and personality traits like Agreeableness and Conscientiousness 8, and specific polymorphisms are associated with sorafenib response in HCC patients 9. These findings indicate ADH1A functions beyond classical alcohol metabolism as a metabolic regulator influencing obesity, cancer progression, and addiction susceptibility.