Application of HLA-class II Genotyping by the Modified PCR-RFLP Method to the Forensic Science

Abstract

The HLA class II antigens(HLA-DR, -DQ, -DP), located in the short arm of chromosome 6, show a great deal of polymorphisms. These antigens have been usually defined by serological procedures (for DR and DQ) using alloantisera or monoclonal antibody and cellular assay procedure (for Dw and DP). Definition of HLA class II antigens became possible at the DNA level using Southern blot hybridization technique with class II antigen cDNA probes. More recently, detection of nucleotide sequence polymorphisms in the HLA class II region has become feasible with the advent of polymerase chain reaction (PCR) technique. The PCR method permits precise and direct analysis of allelic variations with as little as 1 ng of genomic DNA. We earlier reported the modified PCR-RFLP methods (1–3), which were legible and easy to use in the accurate definition of HLA class II (DQA1, DQB1, DRB1 and DPB1) alleles. This method allows discrimination of 36, 91, 946 and 190 combinations, including homozygotes and heterozygotes of the DQA1 (8 alleles), DQB1 (13 alleles), DRB1 (43 alleles) and DPB1 (18 alleles) respectively. In this study, we examined the possibility of HLA-class II genotyping by the modified PCR-RFLP method for DNA samples extracted from hairs, a small volume of whole blood, fresh or old dental pulp tissues.