Description
Glycosylated hemoglobin is the name given to hemoglobin that has been modified by reaction with glucose or similar derivative of this sugar. As blood sugar levels are higher in diabetic patients than in normal individuals, the amount of glycosylated hemoglobin in diabetics can reach four times the value found under normal circumstances and thus the measurement of glycosylated hemoglobin can be used to assess how well the condition is being kept under control. The glycosylated hemoglobin that is found in blood consists of a varity of products, the major one being HbAlc. Studies on this derivative indicate that the sugar may exist as a stable ketimine or as an unstable aldimine, the conversion of one form to the other being achieved by an Amadori rearrangement. In HbAlc the glucose is attached to the N-terminal valine of the beta-chain.