Autologous Bone Marrow transplantation - Blog Science Connections

Detection of MRD by PCR 341
Figure 1. The sensitivity of the PCR assay to detect cells with the t(14;18). A DNA
sample known to have the t(14;18) occurring within the mbr region was first diluted
with a normal DNA sample in various ratios and then PCR was performed using primers
18q21(=) and JH(-) and Taq DNA polymerase (Perkin-Elmer Cetus) for 45 cycles as
described (18). The PCR amplified Samples (5 microliters) were loaded to a 2% alkaline
agarose gel, size fractionated by electrophoresis (60V for 3 hours) and then transfered
onto a nylon membrane. A 5 1
-end radiolabeled probe 18q21(+)II was used to hybridize
with the membrane followed by washing with 2XSSPE/0.1%SDS at room temperature
for one hour and at 65°C for 15 minutes. Autoradiography was carried out with a single
intensifying screen for 16 hours. Lane 1: 1 microgram of DNA sample which was known
to have t(14;18); Lane 2 1:10; Lane 3 1:100; Lane 4 1:1000; Lane 5 1:10,000; Lane 6
1:100,000; Lane 7 1:1,000,000; Lane 8: normal control. Size markers are labeled at the
left side.
the fused bcr/abl gene is transcribed into two types of chimeric
mRNA: one with abl exon 2 linked to bcr exon 2 (designated as L-
6 junction) and the other one with abl exon 2 linked to bcr exon 3
(designated as K-28 junction)(16).