Rapid Detection of IDDM Susceptibility With HLA-DQ β-Alleles as Markers

The allelic forms of the human leukocyte antigen (HLA)–DQ β-chain (DQB1) have been recognized as the best markers of insulin-dependent diabetes mellitus (IDDM) susceptibility. We describe a method that allows the recognition of these DQB1 alleles without the use of either allele-specific oligonucleotide probes or radioactive material. This method determines these alleles by electrophoretically separating restriction enzyme-generated fragments from the polymerase chain-reaction–amplified second exon of the HLA-DQB1 gene, which encodes the first domain of the protein chain. This digestion method, which is simpler and more rapid than the previously adopted hybridization method, is described in detail to enable individuals at any clinical laboratory to quickly ascertain IDDM susceptibility.