Background: ABO genotyping is a useful tool in case of ABO discrepancies and in legal medicine. Recent knowledge of various alleles in the ABO gene has led to the need of a different method that can cover numerous polymorphisms. We performed a polymerase chain reaction using sequencespecific priming (PCR-SSP) with 12 primer sets and evaluated its value in the detection of 8 ABO alleles.
Methods: Genomic DNA was isolated from peripheral blood of 222 unrelated Koreans. Sequencespecific primer sets for the nucleotides 261, 297, 467, 802, 803, and 1059 were selected, and 12 PCR reactions were performed for each sample. Direct sequencing was performed to evaluate the accuracy of discrimination between A(1)(Pro) and A(1)(Leu) and between O(1) and O(1v).
Results: All the ABO genotype patterns were in an exact match with the ABO phenotypes. The results from sequencing and PCR-SSP were equivalent. The allele frequencies of A(1), B, O(1), and O(1v) were 27.25%, 19.82%, 27.25%, and 25.68% respectively. Out of total 121 A(1) alleles, 6 (4.96%) were A(1)(Pro) alleles and 115 (95.04%) were A(1)(Leu) alleles. No A(2), O(2), or CisAB alleles were found in this study.
Conclusions: The proportion of O(1v) allele was similar to that of O(1) allele. This was an unexpected result. We developed a method for detecting 8 ABO alleles by PCR-SSP; the method was accurate and was able to discriminate between A(1)(Pro) and A(1)(Leu) and between O(1) and O(1v).