INS and diabetes mellitus: Patients are also characterized by different autoantibody (AAb) profiles, with four major AAbs (against insulin, GAD65, IA-2 and ZnT8) being detectable in the serum prior to the onset of diabetes.11 Individuals with two or more AAbs have a high risk of progressing to clinical T1D and those with one are at an intermediate risk.11 Among genetic risk factors, the HLA class II locus shows the greatest association with T1D.