DR beta Taq I restriction fragment length polymorphism (RFLP) associated with insulin dependent diabetes mellitus (IDDM).

DNA from insulin-dependent diabetes mellitus patients (IDDM) and healthy control individuals was evaluated using Southern blotting to determine if a disease-associated restriction fragment length polymorphism could be found. Using a DR beta-cDNA probe hybridized to Taq I digested genomic DNA, a 3.7 kb fragment was found in all IDDM patients examined (n = 33). Although a high percentage (47 per cent) of the control population also carried the fragment, nearly one-third of those persons were serotyped as DR2. The possible role of gene regulation in the development of IDDM is discussed.