The Bloodgen Project of the European Union

Blood group genotyping has existed since the mid 1990s following the definition of the molecular basis of the major clinically significant blood group antigens. Initially at least, the application of molecular genotyping for blood group status was applied to situations where blood was difficult or risky to obtain, most notably in prenatal diagnosis in instances of maternal alloimmunisation to RhD, other Rh antigens, Kell and Duffy, and thus used in the clinical management of haemolytic disease of the foetus and newborn (HDFN). The genotyping assays implemented were low-throughput, and generally not applicable for routine use. For genotyping to be considered a viable replacement for routine blood group serology, the development of high-throughput platforms that are automatable is essential. The Bloodgen project was intended to demonstrate the use of gene chip technology as a prelude to the development of a high-throughput, fully automatable genotyping system that may provide a suitable alternative to serological determination of blood group status. The Bloodgen consortium assisted in the development of the commercial product, BLOODchip, which is capable of genotyping 116 blood group-specific single-nucleotide polymorphisms taken from 9 different blood group systems. A small-scale trial was conducted in order to obtain Conformite Europeenne-marking for Rh CcEe, Kell and Duffy diagnostic use, and was successful. Furthermore, genotyping using the BLOODchip platform was shown to be more accurate than the serological typing of the same cohort, which comprised routine blood donors, patients, weak D phenotype individuals and newborns. (C) 2008 S. Karger GmbH, Freiburg i.Br.