CD19 and Burkitt lymphoma: To examine the expression levels of BCR signaling-related genes (BLNK and CD19), SWI/SNF genes (BCL7B and SMARCA4) and GTF2I gene, we performed qRT-PCR analysis of blood samples from a WBS patient at the age of 19 years (who have not yet developed Burkitt lymphoma) and five age/sex-matched control subjects.