A transgenic mouse model of multiple myeloma. Vk*MYCwoLoxP mice have conditional MYC activation in germinal center B cells. Mice progress to indolent myeloma with features highly characteristic of human disease. These mice can be used to study the biology and drug treatment of multiple myeloma, and can be crossed with conditional mice strains expressing Cre recombinase. Transplantable tumor cell lines derived from these mice can be passaged in wildtype C57BI/6 mice and used to assess the efficacy of drugs in more aggressive myeloma tumors.