The HADHA antibody is a tool used to detect the hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha (HADHA), a key enzyme in mitochondrial fatty acid β-oxidation. HADHA, along with HADHB (beta subunit), forms the mitochondrial trifunctional protein (MTP), which catalyzes three steps in fatty acid breakdown: long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD), enoyl-CoA hydratase, and thioesterase activities. Mutations in the HADHA gene are linked to inherited metabolic disorders like trifunctional protein deficiency (TFP) and isolated LCHAD deficiency, which cause life-threatening conditions such as cardiomyopathy, hepatic dysfunction, and hypoglycemia. The HADHA antibody is crucial for research and diagnostics, enabling the detection of protein expression levels, localization, and pathogenic variants via techniques like Western blot, immunohistochemistry, or immunofluorescence. It aids in studying metabolic diseases, mitochondrial dysfunction, and cellular energy metabolism pathways. Recent studies also explore its role in cancer, as altered fatty acid metabolism is a hallmark of tumor progression. Commercially available HADHA antibodies are typically validated for specificity and sensitivity, often targeting epitopes within conserved regions of the human HADHA protein. Proper controls are essential to distinguish between full-length HADHA and degradation products or isoforms.