[Rearrangement of immunoglobulin light chain and heavy chain constant region genes in multiple myeloma].
We analysed immunoglobulin (Ig) gene rearrangements in 28 patients with multiple myeloma by Southern hybridization method. We used 5 probes which cover C kappa and kappa de loci of Ig light chain kappa gene, and JH, 5'S mu and S gamma 3 loci of Ig heavy chain gene. In 11 out of 12 patients with kappa-producing myeloma, DNA rearrangements were observed using C kappa probe. Among them, kappa de region was rearranged in 7 patients and kept germline configuration in 4 patients. In all of 14 patients with lambda-producing myeloma, C kappa region was deleted and kappa de region was rearranged. 5'S mu-probe was very useful for detecting class switch recombination, and furthermore by using S gamma-probe together, S mu-S gamma joining could be detected. In all of 10 patients with gamma-producing myeloma, 5'S mu and S gamma-probes detected the rearranged band of the same size on at least 1 allele, which suggested the presence of S mu-S gamma joinings. In 8 of 10 patients with Bence-Jones myeloma, 5'S mu-probe detected rearranged bands and the presence of class switch recombinations were suggested as observed in other Ig secretory myelomas. In other 2 patients with Bence-Jones myeloma, non-functional class switch recombinations were detected. The results of this study indicated that genotypes corresponded well to phenotypes in multiple myeloma, and further analysis in other types of B cell malignancies will be interesting.
Maruyama
F
F
Department of Internal Medicine, Fujita Health University.
Ino
T
T
Miyazaki
H
H
Nomura
T
T
Shinkai
K
K
Wakita
M
M
Kojima
H
H
Sobue
R
R
Okamoto
M
M
Matui
T
T
D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D015328:Gene Rearrangement, B-Lymphocyte, Light Chain; D005803:Genes, Immunoglobulin / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007127:Immunoglobulin Constant Regions / Q000235:genetics*; D009101:Multiple Myeloma / Q000235:genetics*
D007127:Immunoglobulin Constant Regions