Test Principle – Hemoglobin disorder

Hemoglobin electrophoresis (agarose gel or capillary electrophoresis)

Hemoglobin electrophoresis (agarose gel or capillary electrophoresis) is a well-established technique which is routinely used in clinical laboratories for screening samples for hemoglobin abnormalities. Normal hemoglobin fractions are separated in the following order: Hb A2, Hb F and Hb A. Hemoglobin is a complex molecule composed of two pairs of polypeptide chains.

The type of hemoglobin is determined by the presence of globin chains:

Hemoglobin variants are characterized by the presence of abnormal hemoglobin fractions where substitution of amino acids is caused by a mutation, which leads to modified surface charge and consequently different electrophoretic mobilities. Thalassemias may present abnormal fractions (Hb H or Hb Bart’s) and/or abnormal values for normal hemoglobin (low or high level of Hb A2 for example).