The expression of IGLL5 (immunoglobulin lambda-like polypeptide 5, immunoglobulin lambda-like polypeptide) and T (brachyury homolog, embryonic nuclear transcription factor), was higher in the U-CLL group (top twenty most over-expressed genes in U-CLL as compared to M-CLL) and the expression of TFEC (transcription factor EC) was similarly higher in M-CLL group. This evidence concerns the gene TBX1 and B-cell chronic lymphocytic leukemia.