THE GENOTYPING OF HLA-DQA1 AND HLA-DQB1 USING POLYMERASE CHAIN REACTION-RESTRICTION FRAGMENT LENGTH POLYMORPHISM COMBINED WITH GROUP-SPECIFIC PRIMERS AMONG KOREANS

The polymorphisms of HLA genes are mainly found in the second exons encoding for distal extracellular domains of the HLA classII molecules, The accurate typing of the polymorphisms of HLA genes is not easy because of the small differences in the nucleotide sequences among alleles, The several genotyping methods are not sufficient for the accurate typing of the HLA genes, In this study, the HLA-DQA1 and HLA-DQB1 genotypes were determined in 18 control cell lines and 112 unrelated Koreans using polymerase chain reaction-restriction fragment length polymorphism, Amplified DNA fragments were digested with allele specific restriction enzymes and subjected to electrophoresis in 12% polyacrylamide gels, The results of control cells correlated well with data previously reported, 7 alleles and 20 genotypes in the DQA1 gene, 16 different alleles and 48 genotypes in the DQB1 gene were found among Koreans, The most frequent alleles were DQA1*0301 and DQB1*03032 and heterozygosity was 0.795 and 0.893 in DQA1 and DQB1 respectively, The observed genotypes of DQA1 and DQB1 genes were in agreement with the expected genotypes and conformed to the Hardy-Weinberg rule, As to the results of this study, the polymerase chain reaction-restriction fragment length polymorphism method provides relatively simple, fast and practical tool for accurate determination of HLA genotypes, Moreover these results-allele and genotype frequency and heterozygosity of HLA DQ genes might be useful for database study before using them for individual identification and transplantation immunity among Koreans.