Several biomarkers have been proposed for ultrasensitive real-time detection of pancreatic beta cell injury in vivo [1–3] The biomarker with the longest track record thus far is the type 1 diabetes autoantigen glutamic acid decarboxylase 65kD (GAD65): in rodent models, GAD65 is discharged proportionately to the experimentally-induced degree of beta cell destruction [3]. This evidence concerns the gene GAD2 and type 1 diabetes mellitus.