Autoantibodies to GLUT-2 have been detected in most patients with recent-onset type 1 diabetes63 and reactivity of β-casein T-cell lines to human insulinoma extracts and GLUT-2 peptide has been reported.59 However, the full implications of these findings are open to speculation because β-cell autoantibodies may not necessarily be pathogenic: rather, they may represent reproducible biomarkers of the pathogenesis.2 This evidence concerns the gene SLC2A2 and pancreatic insulinoma.