Work Package 1:
Blood Antigen Genotyping
At present, blood group types are determined by tests that use antibodies. A different test is required for every blood group type. There are many different blood group types and to test them all using antibodies is cumbersome and expensive. Consequently, at present only 1 in 6 NHSBT donors have most of their blood group types determined. If we are to take all blood group types into account when matching patients to donated blood then we need to be able to measure all the blood group antigens of patients and of the vast majority of the million donors.
It is now possible to work out a person’s blood group types by testing his or her DNA. Although humans have approximately 20,000 genes, less than 50 of these determine blood group types. Before now measuring variation in blood type genes has been expensive and slow. However, a major advance has been made by the Blood transfusion Genomics Consortium (BGC), whose members have developed a cheap, high throughput method for measuring the particular DNA letter changes that cause blood group differences.
An instrument called GeneTitan, which can read the DNA sequence changes has been installed at NHSBT is now used to determine the blood group antigen types from nearly 100,000 donors of blood. Members of the Blood transfusion Genomics Consortium at the Brigham and Woman’s Hospital have with the New York Blood Centre developed software called bloodTyper that is able to compute blood group types from the measurements made by GeneTitan instrument.
By combining GeneTitan with bloodTyper we will have created a panel of 100,000 donors for whom all blood group types have been determined to facilitate extended blood group antigen matching for patients who require regular transfusions of blood.