TLX1 level of expression. RQ-PCR quantification of TLX1 transcripts normalized for ABL in 171 adults (□) and 93 children (○) T-ALL samples, 30 B-ALLs (▵), 21 AMLs (♢), 5 normal bone marrows (), 10 normal peripheral blood lymphocytes (−) and 5 normal thymi (+). Results are expressed as TLX1/ABL ratio and displayed on a logarithmic scale. A clear difference of a minimum of 1 log-fold expression separates the TLX1-high from the TLX1-low samples. The cut-off value of 1.00 ABL is displayed (----). Samples with detectable TLX1 signal but inferior to 1.00× 10⁻⁵ were considered negative, based on plasmid dilutions experiments.