Application of ABO genotyping in determination of ABO subgroups

Kim, Mun Jeong; Shin, Jeong Won; Kim, Young Hwan; Kim, Hyun Ok; Cho, Sung Ran; Kim, Whi Jun

Abstract

BACKGROUND
The knowledge about the nucleotides sequence of 9th chromosome that regulates the phenotype of ABO blood group has made the ABO genotyping possible. Since the genotyping can be done with only a small amount of DNA sample, it was primarily applied to the field of forensic medicine. When applied to the blood bank, it is useful in the resolution for ABO discrepancies between the cell and serum typing and determination of A and B subgroups. Rapid ABO genotyping using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and its value in determination of ABO subgroups is presented.
METHODS
ABO genotyping was performed in seven patients and three families, seven were the cases of ABO discrepancies in routine ABO grouping and three families were for the confirmation of the ABO group. To identify the 261th nucleotide, a 252 bp PCR amplifed fragment was amplified by PCR and digested with Kpn I. For 703th nucleotide, a 128 bp PCR amplified fragment was designed and digested with Alu I. To determine the ABO genotype, the patterns of digestion in DNA fragment were examined.
RESULTS
Among the seven cases of ABO discrepancies, B3 and Ael were two cases each. Weakened B due to leukemia was the one, and the other two cases were cis-AB and Am. The three families for confirmation of the ABO group were acquired B due to infection one family, cis-AB two families.
CONCLUSIONS
ABO genotyping is a rapid and reliable method that can be used in the case of ABO discrepancies and determination of ABO subgroups.