Polymorphism of the genes encoding the alpha, beta, and gamma chains of the human T-cell receptor (TCRA, TCRB, and TCRG), insulin gene (INS), and three closely linked polymorphic genes on chromosome 11q23, Thy-1 (THY1), T3-D (CD3D), and c-ets proto oncogene (ETS1) were investigated among 56 unrelated patients with insulin-dependent diabetes mellitus (IDDM) and 48 healthy controls.
A highly polymorphic microsatellite marker mapping to the TCRBV6.7 gene and a TCRB C-region RFLP were used to genotype the members of a total of 21 multiplex IDDM families from two different geographical areas.