However, there still remain some blood-group systems for which genotyping remains challenging because the genes encode enzymes involved in the modification of carbohydrate chains (eg, ABO, H, I, GLOB), or blood-group antigens
are determined by large insertions, deletions, or hybrid genes from recombination of homologous genes (eg, RHD, RHCE, GYPA, GYPB).
Researchers explain that most blood banks still use a century-old blood approach to blood typing which identifies blood-group antigens
on red blood cells--proteins that must match in donor and recipient to avoid potentially serious transfusion reactions.
Other remaining proteins are removed by a displacement chromatographic process that strips away blood-group antigens
and other proteins, so Hemolink can be used by all patients regardless of blood type.
Read notes that the gene cloning may pave the way for identification of other blood-group antigens
present on cancer cells, expanding the potential for treatment.
Rare blood is blood that is negative for multiple blood-group antigens
or lacks a high-frequency antigen.