Use of the polymerase chain reaction for typing allelic variants of the human HLA-DQA1 by hybridization with oligonucleotide probes, specific for specific alleles]

Class II HLA molecules are the most useful markers for susceptibility to different autoimmune diseases, including insulin-dependent diabetes mellitus (IDDM) and rheumatoid arthritis (RA). Polymerase chain reaction and hybridization with a set of allele-specific oligonucleotide have been used for analysis of allelic sequence variation. The analysis of frequencies of HLA-DQA1 alleles among 10 patients of the russian population revealed a uneven distribution. We have developed a method for preparing non-radioactive oligonucleotide probes with terminal deoxynucleotidyl transferase and Bio-11-dUTP. Comparison of biotinylated and 32P-labeled hybridization probes gave the same sensitivity for HLA-DQA1 typing of amplified DNA. Amplification of the HLA-DQA1 gene has been successful on 10 pg of total DNA. This amount of DNA is close to the amount of DNA in a single cell. Alternatively, HLA-DQA1 typing could be based on the analysis of buccal cells of saliva that would avoid the problem of individuals who object to giving blood samples.