Syrian hamster lymphocyte cytogenetic technique and effects of blood storage on mitotic index

Summary The Syrian hamster has a diploid chromosome complement similar to humans in both number (2N=44) and morphology. For comparative mutagenic studies with humans, a repeatable lymphocyte chromosome technique involving laboratory mammals is desirable. The reported hamster lymphocyte cytogenetic technique appears technically uncomplicated and repeatable while providing a sufficient number of metaphase cells for quantiative analysis. In order to determine the effects of storing whole-blood (in culture media) for varying time periods at 8°C prior to adding a mitogen, the mitotic index was calculated following a 48-h culture period. Results indicated the storage up to six days can still result in a mitotic index adequate for cytogenetic analyses.