Specificity of acquired clonal chromosome abnormalities in New Zealand Black mice

New Zealand Black (NZB) mice, an inbred strain characterized by immunological dysfunction and lymphoreticular malignancy, also develop populations of aneuploid spleen cells. In detailed cytogenetic analyses performed on 10 NZBs, the chromosomally abnormal cells were found to be clonally related within each mouse. Moreover, the karyotypic changes observed were highly non-random, usually involving the 15 (10/10 mice), 2 (8/10 mice), 16 or 17 (9/10 mice), and sex (6/10 mice) chromosomes. These observations suggest an important relationship between chromosomal alterations and tumorigenesis in NZB mice and emphasize the role of chromosome 15 in murine abnormal lymphoreticular proliferations.