A new method for starch gel electrophoresis of human hemoglobins, with special reference to the determination of hemoglobin A2.

ONSIDERABLE EVIDENCE IS now available indicating that normal adult hemoglobin (hemoglobin A) is heterogeneous. Sharp and well-defined fractions of hemoglobin A, designated A2 and A3, were obtained by Kunkel (11), who used insoluble potato starch as a supporting medium for electrophoresis. Kunkel also was the first to measure quantitatively the amount of hemoglobin A2 and to correlate increases in the amount of hemoglobin A2 normally present with the presence of the gene for thalassemia. Studies from other laboratories have confirmed the usefulness of potato starch as a supporting medium for the detection and quantitative measurement of subfractions of hemoglobin A (4, 6, 8). A method using starch gel as a supporting medium for the electrophoresis of serum proteins was developed by Smithies (19). It was found to have great advantages over conventional methods of protein electrophoresis because of superior resolution and fractionation of the protein components. This method was subsequently adapted by us to electrophoresis of hemoglobins (6). A recent publication by Owen and Got (14) has confirmed the usefulness of starch gel as a supporting medium for hemoglobin electrophoresis. The method to be described was modified from that presented earlier (6) by the use of a discontinuous buffer system, using tris-