About 60%-90% of type I (insulin-dependent) diabetics have antibody against islet cell cytoplasmic glycoprotein (“islet cell autoantibody”) at the time of diagnosis, and many of those initially without this antibody develop it later. This antibody disappears within 2 years after appearance in 85%-90% of type I diabetics. It has also been reported in about 20% of type II diabetics and about 10% of gestational diabetics at time of diagnosis. About 30%-50% of children have autoantibody against insulin (antiinsulin antibody) at time of diagnosis before beginning insulin therapy and some (much less than formerly) develop it after using therapeutic insulin. Some patients have autoantibodies against beta cell surface antigen (beta cell antibodies). Over 95% of type I patients possess the human lymphocyte antigen (HLA) DR3 or DR4. However, at present these autoantibodies and HLAs are not being widely used in clinical medicine or in diagnosis.