Implication of novel RH alleles in blood transfusion therapy

The Rh blood group system is one of the most complex and clinically significant blood group systems, with numerous alleles that can affect compatibility between donors and recipients. Over the years, with advancements in molecular techniques an increasing number of novel RH alleles arising from genetic variations in the RHD and RHCE genes have been discovered. These novel alleles can lead to discrepancies between serological and genotypic typing methods and may result in altered Rh protein structure or expression levels, potentially affecting antigen presentation and immune recognition. In general, new alleles have emerged with advances in molecular techniques with very little information about the antigens they encode or the formation of antibodies. Understanding these functional implications is crucial for predicting compatibility and managing the risk of alloimmunization and transfusion reactions effectively. The risk of alloimmunization is often associated with the type of variant Rh antigen that the new allele encodes, so further serological and clinical studies would be valuable to determine its clinical significance. This review aims to explore the implications of novel RH alleles in transfusion therapy and to discuss future directions, including the incorporation of 3D analysis and computational tools to predict the functional consequences of novel RH alleles. These tools can aid in the interpretation of molecular data and provide insights into the potential clinical phenotype associated with specific variants.