Subclones of DN-hTERT–transduced T cells display lower DN-hTERT gene expression. The level of GFP expression is decreased in DN-hTERT–GFP–transduced clones. Two clones isolated from limiting dilution of MoT-72 transduced with DN-hTERT (Asp712Ala, Val713Ile)–GFP (top middle and top right), displayed a lower GFP expression than the average GFP level expressed by the bulk culture right after transduction (top left). Graphs are representative of the GFP expression by all DN-hTERT clones obtained. All DN-hTERT (Asp712Ala, Val713Ile)–GFP–expressing clones died after cloning. The GFP expression remained high in clones isolated from cloning of MoT-72 transduced with hTERT-GFP (bottom middle and bottom right). This level of GFP expression was equal to the GFP expression level after transduction (bottom left). Graphs are representative of 16 hTERT-GFP–expressing clones analyzed.