Elucidation of the molecular bases of the Rh system and its contribution to transfusion and obstetric medicine—historical and current perspective: a review

Abstract

The Rh System, the most polymorphic of the human blood groups, is of major clinical interest in transfusion and obstetric medicine due to the participation of Rh antibodies in phenomena of immune mediated red blood cell destruction. Rh antigens are highly immunogenic and are often involved in haemolytic transfusion reactions and in the Haemolytic Disease of the Newborn (HDN). Since the cloning and sequencing of the RH genes in the early 1990s and the development of numerous molecular techniques for the analysis of genetic polymorphisms, a plethora of allelic variants has been identified over time. Genotyping strategies are being increasingly incorporated in the field of transfusion medicine and have shown a great capacity to overcome the limitations of serology. In house and commercial DNA-based developments allow the characterization of clinically significant allelic variants and have proven to be remarkable for accurate donor - recipient matching to prevent alloimmunization, determining the risk for HDN or guiding immunoprophylaxis among other applications. In this work, the molecular bases of the Rh system and the new allele discoveries throughout this time will be reviewed. Also, the impact of the molecular identification of different RH allelic variants in the field of transfusion and obstetric medicine will be summarized.