Multiplex-PCR products of TCRD-TLX1 junctions in T-ALLs. Top lanes: TCRD-TLX1 junctions among 8 TLX1-high T-ALLs. Next to these are loaded 10 representative products of the same PCR experiment, performed on 30 TLX1-low samples. No TCRD-TLX1 junction was amplified among the 30 TLX1-low T-ALLs tested. Bottom lanes: Logarithmic dilutions estimated the PCR sensitivity to reach 10^−3/−4. The DNA ladder appears on the left.