Usefulness of long-distance inverse polymerase chain reaction for molecular detection of 14q32 translocation in a clinical setting.
All mature B-cell leukaemias and lymphomas have a clonal Ig gene recombination, and half of them have a reciprocal chromosomal translocation involving the 14q32 locus. The 14q32 translocation partners are variable, such as BCL-2, BCL-1 and BCL-6, thus accounting for the difficulty in molecular detection by the current genomic polymerase chain reaction (PCR) method. To identify B-cell clones efficiently with an Ig gene rearrangement and reciprocal inter-chromosomal translocation, we verified the usefulness, in a practical laboratory setting, of our modified long-distance inverse (LDI) PCR method for detecting IgH gene rearrangements involving inter- and intra-chromosomal segments. The total run time of this LDI PCR method was 5.5 h. Using 24 samples of mature B-cell leukaemias and lymphomas, the modified LDI PCR gave clonally rearranged amplicons in 83 % (20/24) of cases. Direct sequencing results of the amplicons revealed inter-chromosomal translocations in 5 cases (25 %) and intra-chromosomal rearrangements in the remaining 15 cases (75 %). The partners of the inter-chromosomal translocation consisted of the 11q13.3 segment containing a partial BCL1 sequence in 3 cases; 18q21.3 segment containing a partial BCL2 sequence in one case; and a segment of 7ql1.2 in one case. We present an LDI PCR-based methodology for the efficient identification of 14q32 translocations, with modifications to reduce the total run time to within one day.
Ishizaki
Akiko
A
Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
Sugahara
Kazuyuki
K
Tsuruda
Kazuto
K
Hasegawa
Hiroo
H
Yanagihara
Katsunori
K
Tsukasaki
Kunihiro
K
Yamada
Yasuaki
Y
Kamihira
Shimeru
S
D001402:B-Lymphocytes; D001483:Base Sequence; D002883:Chromosomes, Human, Pair 14; D015321:Gene Rearrangement; D005803:Genes, Immunoglobulin; D006801:Humans; D015448:Leukemia, B-Cell / Q000235:genetics; D016393:Lymphoma, B-Cell / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D014178:Translocation, Genetic