Abstract |
The L5178Y/TK t/- TK-/- mouse lymphoma mutagen assay, which allows selection of forward mutations at the autosomal thymidine kinase (TK) locus, uses a TK t/- heterozygous cell line, TK t/- 3.7.2C Quantitation of colonies of mutant TK-/- cells in the assay forms the basis for calculations of mutagenic potential of test compounds. The authors have evaluated the banded karyotypes of the parent TK t-/- heterozygous cell line, as well as homozygous TK-/- mutants, in order to relate the genetic and morphological properties of mutant colonies. The parent cell line displays karyotype homogeneity, all cells containing normal mouse chromosomes, readily identifiable chromosome rearrangments, and cell line specific marker chromosomes. |