EtBr stained agarose gel with semi-nested PCR products from prelysis and postlysis BM harvest and from peripheral blood (pb) and/or bone marrow (bm) samples at time of BMT, post-BMT follow-up (F/U), and relapse in patients with MCL. (A) Patient no. 1705 samples tested with the relevant ASO primer. The ASO primer specific for patient no. 1705 did not amplify three different MCL patients used as negative controls. (B) Patient no. 1846 samples tested with the BCL-1/IgH primers. No clonal product was seen in the normal donor PBL used as negative control. Negative control, neg. ctl.; M, molecular weight marker.