A PCR-SSOP method for typing of HLA-A, -B, and -DRB1 genes in Japanese population

Abstract

A PCR sequence-specific oligonucleotide probing (PCR-SSOP) method has been adopted for typing of HLAA, -B, and -DRB1 genes in the Japanese population. The method targets alleles observed at more than 0.1% gene frequency in the Japanese population. Using 13, 24, and 17 probes for HLA-A, -B, and -DRB1 genes, respectively, the method enabled us to discriminate HLA alleles or at least serological groups even in heterozygous samples. We set the washing temperature for a total of 54 probes to a single temperature (55oC). Approximately one hundred known samples for all three HLA genes could be typed correctly except one variant sample for HLA-A. A PCR primer did not work efficiently for one of the hetrozygous alleles of the variant sample because it has a sequence substitution in the target portion of the intron. The method could be improved using mixed primers that also target the variant sequence. It is also possible to amplify DNA efficiently and type HLA genes using blood samples on filter paper.