title: Chromosomal evolution in secretory and nonsecretory subline of MOPC 21.
abstract: Murine myeloma cell lines are noted for the instability of their immunoglobulin genes and the production of nonsynthesizing variants. In this study, the synthesizing line P3-X63-Ag8 (P3) and its nonsynthesizing subline X63-Ag8-653 (653) were karyotyped and rearrangements of the immunoglobulin carrying chromosomes were investigated. Loss of immunoglobulin synthesis was associated with a reduction in the number of immunoglobulin-carrying chromosomes. When these findings were analyzed in light of published molecular data, it appeared that loss of immunoglobulin synthesis in 653 probably occurred as a result of immunoglobulin gene loss. An unusual finding was the absence of the t(12;15) chromosome in both P3 and 653 cell lines. It was concluded that the t(12;15) chromosome, carried by MOPC 21, has evolved into an unrecognizable form.
authors.affiliation: Department of Haematology, School of Pathology of the University of the Witwatersrand, Johannesburg, South Africa.
authors.forename: B E
authors.initials: BE
authors.lastname: Lambson
authors.forename: R
authors.initials: R
authors.lastname: Bernstein
authors.forename: B V
authors.initials: BV
authors.lastname: Mendelow
mesh_terms: D000818:Animals; D000906:Antibodies / Q000378:metabolism; D002872:Chromosome Deletion; D007136:Immunoglobulins / Q000096:biosynthesis* / Q000235:genetics; D007621:Karyotyping; D051379:Mice; D009101:Multiple Myeloma / Q000235:genetics* / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D000906:Antibodies; D007136:Immunoglobulins