The HANABI-PV Metaphase Auto-Spreader allows for optimization of environmental conditions for the preparation of metaphase chromosome spreads. Temperature, humidity and airflow are set and rapidly stabilize, thus ensuring that when chromosomes are dropped and spread on microscope slides, they are dried in a consistent and reproducible manner. Excessive spreading and chromosome overlaps are minimized, facilitating better yields of metaphase analysis. The samples tubes and slides are tracked by bar codes (unique feature). The chromosome spreading process for conventional FISH, CGH and G-banding analysis of samples derived from blood cells or bone marrow samples is now more streamlined and consistent. Crossing of the chromosomes is minimal, and, after automated spreading, can be analysed on the completed slide. Protocols requiring that cells and chromosomes are spread on the entire slide can be achieved using an optional tilted slide block.