Hemoglobin electrophoresis is a laboratory technique used to separate and identify the different types of hemoglobin in blood. Hemoglobin is the oxygen-carrying protein inside red blood cells. While most adults have hemoglobin A (HbA), some people inherit changes in the genes that produce hemoglobin, leading to variants such as hemoglobin S (linked to sickle cell disease), hemoglobin C, hemoglobin E, or altered levels of normal fractions like HbA2 and HbF. Detecting these variants is critical for diagnosing conditions like sickle cell disease and thalassemias, which can affect oxygen delivery, red blood cell survival, and overall healthspan.
The principle of electrophoresis is straightforward: charged molecules, such as hemoglobin proteins, move at different speeds when an electric current is applied to a gel or capillary. By observing how far each type travels, laboratory specialists can determine which hemoglobins are present and in what proportion.
Earlier methods used paper or cellulose acetate strips, and later acrylamide gels, which provided reliable but relatively slow results. Today, capillary electrophoresis offers faster, automated, and highly sensitive separation. This modern approach not only detects common variants but also measures subtle differences in hemoglobin fractions with great precision. For example, elevated HbA2 suggests beta-thalassemia trait, while increased HbF may indicate certain hereditary or acquired conditions.
Recent innovations have gone further, with microchip-based and point-of-care devices allowing hemoglobin testing outside of major laboratories. These portable systems can provide rapid results in regions with limited resources, which is particularly important in areas where hemoglobin disorders are highly prevalent.
That said, no method is perfect. While electrophoresis is considered the gold standard for diagnosing most hemoglobinopathies, some rare variants migrate in patterns similar to others and may be missed. In such cases, DNA analysis or advanced mass spectrometry can confirm the exact genetic or structural change.
In clinical practice, hemoglobin electrophoresis is used for newborn screening, evaluation of unexplained anemia, confirmation of suspected sickle cell or thalassemia, and prenatal testing in families with a history of hemoglobin disorders. Because these conditions can have lifelong health implications, identifying carriers and affected individuals early allows for more precise treatment and informed reproductive decisions.
