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A T cell receptor beta chain polymorphism is associated with patients developing insulin-dependent diabetes after the age of 20 years.

S A McMillan·C A Graham·P J Hart·D R Hadden·T A McNeill
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Abstract

We have studied the BglII polymorphism near the T cell receptor beta chain constant region (TcR-C beta) gene, HLA-DR genotypes and certain autoimmune features in 102 patients with type I (insulin-dependent) diabetes. There was a significant decrease in the frequency of the 1:1 genotype (P = 0.008) and an increase in the 1:2 genotype (P = 0.03) of the BglII TcR polymorphism in the group of patients who developed type-I diabetes after the age of 20 years. This group of patients also showed an increased incidence of autoantibodies (especially islet cell antibody), a family history of diabetes and the presence of other autoimmune diseases. The frequency of this polymorphism in patients who developed type I diabetes before the age of 20 years was similar to a non-diabetic group. These results suggest that there are two genetically distinct groups of patients with type I diabetes. HLA-DR3 and HLA-DR4 genotypes were also increased in the diabetic patients but no significant difference was observed between HLA-DR genotypes, the TcR-C beta genotypes, the age of diagnosis or with other autoimmune features. Patients developing type I (insulin-dependent) diabetes after the age of 20 years have an additional genetic susceptibility for diabetes associated with the TcR-C beta gene.

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AdolescentAdultAge FactorsAutoantibodiesChildChild, PreschoolDNA ProbesDiabetes Mellitus, Type 1FemaleGenotypeHLA-DR AntigensHumansInfantMalePolymorphism, GeneticPolymorphism, Restriction Fragment LengthReceptors, Antigen, T-CellReceptors, Antigen, T-Cell, alpha-betaComparative StudyJournal Article

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S A McMillan, C A Graham, P J Hart, D R Hadden, T A McNeill. 1990. A T cell receptor beta chain polymorphism is associated with patients developing insulin-dependent diabetes after the age of 20 years.. https://doi.org/10.1111/j.1365-2249.1990.tb05486.x

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