Analysis of key p53 transcriptional target genes, such as CDKN1A, BAX and TNFRSF10A and TNFRSF10B [21,30,31], revealed mutation of CDKN1A in only 1 B-CLL patient (0.9%) (Tables 1 and 2), while no mutations were detected in BAX, as well as of genes encoding death receptors TNFRSF10A and TNFRSF10B. This evidence concerns the gene CDKN1A and B-cell chronic lymphocytic leukemia.