Molecular cloning of a polymorphic DNA endonuclease fragment associates insulin-dependent diabetes mellitus with HLA-DQ
A BamHI 3.7-kilobase (kb) fragment detected by an HLA-DQ β-chain complementary DNA (cDNA) probe and negatively associated with insulin-dependent diabetes mellitus (IDDM) was cloned and sequenced to localize the polymorphism to BamHI sites in intervening sequences of an HLA-DQ β-chain gene. A probe of the first intervening sequence (IVS 1) showed the BamHI 3.7-kb fragment in 6 of 17 HLA-DR3/4 contr