Using Genotyping to Identify an A1B(weak) Blood Group

Cho, Chi Hyun; Yoo, Byong Joon; Yun, Seung Gyu; Choi, Gye Ryung; Choi, Jae Yeoul; Kim, Jang Su; Lim, Chae Seung; Kim, Young Kee; Lee, Kap No

Abstract

Since an exact ABO blood type match is essential for transfusion therapy, any ABO discrepancies should be resolved prior to the issuing of blood. The authors confirmed the ABO blood group of a 50-year-old male using genotyping. On a routine blood group test, the cell type was A+; however, anti-B was undetected in his serum. To determine the cause of this ABO discrepancy, an adsorption elution test and saliva test were performed. The presence of a weak B substance was suspected despite no evidence of the B antigen on red blood cells. Polymerase-chain-reaction restriction-fragment-length-polymorphism (PCR-RFLP) and sequencing analysis of exons 6 and 7 demonstrated that his blood type was A1Bweak (the A allele tested as the A105 subtype, while the B allele was most similar to the B302 subtype). Again, using genotyping, we subsequently confirmed the A1Bweak blood type in a leukemic patient who was in complete remission.