Diagnostic Tests

Anti‐GAD 65 (Glutamate Decarboxylase)

ANTIGENS / BIOMARKERS

Anti-Glutamate Decarboxylase

SKU / TEST CODE

GAD

PROCEDURE / TECHNIQUE

Cell-Based Assay (CBA)

REFERENCE RANGE

Qualitative Analysis: Neg /Low Positive/Med Positive/High Positive

SENSITIVITY / SPECIFICITY

TBD

CLINICAL ASSOCIATIONS

Mitogen’s assay for anti‐Glutamate Decarboxylase (GAD) is an autoimmune diagnostic test that detects autoantibodies to GAD. The detection of autoantibodies against GAD is found in Type 1 diabetes mellitus, ataxia, progressive encephalomyelitis with rigidity and myoclonus (PERM), limbic encephalitis, and epilepsy. 70%-90% of patients with newly diagnosed type 1 diabetes mellitus and those defined as preclinical cases produce autoantibodies to GAD. They have a high predictive value with respect to the individual risk of developing type 1 diabetes. GAD65 (Glutamate decarboxylase or glutamic acid decarboxylase) is an enzyme that decarboxylates glutamate into GABA and CO2. GAD65 is localized in the brain (where GABA is used as a neurotransmitter) and in the insulin-producing β-cells of the pancreas.

Reference: Kim J, Richter W, Aanstoot HJ, Shi Y, Fu Q, Rajotte R, et al. (December 1993). “Differential expression of GAD65 and GAD67 in human, rat, and mouse pancreatic islets”. Diabetes. 42 (12): 1799–808. doi:10.2337/diab.42.12.1799. PMID 8243826.

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