Which abnormal type of Hgb migrates to the same position as Hgb S?

Hemoglobin DPunjab is classified as an abnormal hemoglobin variant that exhibits similar electrophoretic properties to Hemoglobin S (Hgb S). Both Hgb S and Hgb DPunjab have altered electrical charges due to their amino acid substitutions, which causes them to migrate to the same position on an electrophoresis gel under standard testing conditions.

In contrast, while Hemoglobin C, Hemoglobin OArab, and Hemoglobin E are indeed abnormal hemoglobins, each of these variants has different charges and structures compared to Hgb S. As a result, they migrate differently during electrophoresis and are thus distinguishable from Hgb S on an electrophoretic gel.

Understanding these relationships is vital for accurate diagnosis and management of sickle-cell disease and other hemoglobinopathies, as recognizing the presence of specific types of abnormal hemoglobin can inform clinical decision-making and the potential need for further testing.