Aim of BloodGen: To validate and standardise molecular genotyping approaches to large-scale blood group diagnosis and to prove its superiority over currently applied serological testing.

Current blood transfusion practice relies on the serological definition of blood group status, with the cross-match test remaining the final check that donated blood and transfusion recipient are compatible.   Despite these serological procedures being highly accurate, routine testing does not cover all clinically significant blood group antigens; it is not practical or economic to test every blood donation for every blood group. 

As a consequence patients with rare blood group antigens can become alloimmunised due to transfusion of incompatible blood, although fortunately this occurs at a low rate. 

If alloimmunisation occurs, such patients will face a problem if they require further transfusions or have a blood group incompatible pregnancy.   

The BloodGen Consortium draws together most of Europe’s experts of molecular blood grouping.  The project is looking at methods of molecular genotyping as a possible alternative to serological definition of blood group status. 

This approach can be applied to blood group definition, as all clinically significant blood groups have been defined at the level of the gene. 

BloodGen will provide a series of diagnostic tests that use a DNA-based technical platform, using conventional high throughput genotyping. 

The project will involve the fabrication of gene chips and development of fluorescent PCR tests for blood group alleles.  The strategy will be to identify all clinically relevant blood groups on donation, to provide a blood group genotype for all patients to enable accurate transfusion (especially in the case of patients carrying low-frequency blood group alleles) and to reduce the incidence of alloimmunisation. 

Following a pre-clinical trial on a cohort of donors from across the EU, the long term objective will be the introduction of molecular blood group definition into routine use within the EU, which will improve the safety of blood transfusion.