Abstract
The karyotypes of original solid and transformed ascites type tumors of plasma cell neoplasm X5563 were compared with special regard to the electrophoretic serum pattern of mice bearing these tumors. Both lines were characterized by a wide tetraploid range of chromosome number variation. The chromosome number in stemline cells was 84 in both solid and ascites lines, but their karyotypes were different. The solid form had one submedian metacentric (SM) and one subtelocentric (ST) chromosome as markers, and the latter had two SM-, one ST- and one minute (m). The electrophoretic pattern of γ-globulin found in mice bearing solid and ascites tumor was similar. The observed stability of γ-globulin was discussed in relation to the tetraploidy ofthe neoplasms.
