A joining - diversity - joining complex generated by inversion mechanism and a variable - diversity complex in the β - chain gene of the human tcell receptor

We have analysed an inactive allele of the β-chain gene of the T-cell receptor in a human T-cell line HPB-ALL. Comparison with germline sequences showed that HPB-ALL has a joining (J)-diversity (D)-J complex recombined in head-to-head configuration and a variable (V)-D complex in tail-to-tail configuration. These results demonstrate that the inversion mechanism functions in the β-chaln gene of the T-cell receptor. The presence of the V-D complex suggests that V-D recombination could occur prior to D-J recombination although there is no definite proof that the V-D complex is an intermediate to form the V-D-J complex.