Detection of Novel Gene Rearrangement in the c-myc and c-fos Region in an IgA ^|^kappa; Type Multiple Myeloma

Unique gene rearrangements affecting the c-myc and c-fos oncogenes were detected at the genomic DNA level in one IgA κ type multiple myeloma among 15 cases of multiple myeloma. The c-myc locus, which maps to chromosome 8g24, showed a rearranged and amplified 20kb band in an EcoRI restriction digest. The c-fos oncogene, which maps to 14g24, showed a rearranged and amplified 8.0kb band in a BamHI restriction digest, together with a rearrangement and amplification of Ig heavy chain Cμ DNA, which maps to 14g32. These results suggested abnormalities in both chromosomes 8q and 14q. To date, rearrangements of the c-fos gene have not been reported in multiple myeloma. The results obtained here agree with previous reports of diverse karyotypic abnormalities in multiple myeloma.