Polymorphism study of TCR alpha and gamma genes in insulin dependent diabetes mellitus (IDDM) multiplex families.

T-cell receptor (TCR) alpha and gamma genes polymorphisms were analysed by Restriction Fragment Length Polymorphism (RFLP) in 10 Insulin Dependent Diabetes Mellitus (IDDM) multiplex families. TCR alpha and gamma alleles distribution does not significantly differ between affected and non affected children. Furthermore there was no excess of C alpha or V gamma allele sharing in affected sib pairs. Therefore the T-cell receptor alpha and gamma chain alleles studied do not seem to affect IDDM susceptibility per se.