total glycated haemoglobin (GHb)

Last reviewed 01/2018

Total Glycated hemoglobin

  • defined as hemoglobin with glucose bound to any of these potential sites
    • HbA1c is a subset of glycated hemoglobins. It is defined as hemoglobin with glucose bound at the beginning (N-terminal) of the ß-chain

    • total glycated hemoglobin (total GHb) will include HbA1c plus all the other hemoglobins (including haemoglobin variants) that have glucose bound to lysine side chains and/or to the N-terminal of the alpha-chain
      • HbA1c is the major subfraction of the glycated normal hemoglobin (HbA1)

    • generally about half of the glucose is bound to the HbA1c position with the other half bound at 3 or 4 other sites (lysines)

Reference interval:

  • Diabetes > =9.0%
  • Risk of diabetes 7.3 to 9%
  • Healthy adult: 3.9% to 7.3%

Note that reference ranges may vary between laboratories and based on the assays used.