Which laboratory method is commonly used for blood group typing?

The hemagglutination assay is the most commonly used laboratory method for blood group typing because it effectively detects the presence of specific antigens on the surface of red blood cells. This method relies on the principle that red blood cells will agglutinate (clump together) when exposed to antibodies that are specific to their surface antigens.

In blood group typing, a sample of blood is mixed with known antisera that contain antibodies for specific blood group antigens (such as A or B). If the corresponding antigen is present on the red blood cells, the antibodies will bind to them, leading to visible agglutination. This straightforward and rapid method allows laboratories to accurately determine an individual's blood type, which is critical for safe blood transfusions and organ transplants.

Other methods listed, while useful in various contexts, are not the standard for routine blood group typing. Polymerase chain reaction (PCR), for example, is primarily used for genetic analysis and pathogen detection rather than for typing blood groups. Enzyme-linked immunosorbent assay (ELISA) is more commonly associated with detecting proteins or antibodies in serum rather than determining blood types. Flow cytometry is a sophisticated technique used for detailed cell analysis but is not typically employed for routine