Editing Cytogenetics (section)

====Slide preparation====
Cells from [[bone marrow]], blood, amniotic fluid, [[cord blood]], tumor, and tissues (including skin, [[umbilical cord]], chorionic villi, liver, and many other organs) can be cultured using standard cell culture techniques in order to increase their number. A [[mitotic inhibitor]] ([[colchicine]], [[colcemid]]) is then added to the culture. This stops cell division at [[mitosis]] which allows an increased yield of mitotic cells for analysis. The cells are then centrifuged and media and mitotic inhibitor are removed, and replaced with a hypotonic solution. This causes the white blood cells or fibroblasts to swell so that the chromosomes will spread when added to a slide as well as lyses the red blood cells. After the cells have been allowed to sit in hypotonic solution, Carnoy's fixative (3:1 [[methanol]] to [[acetic acid|glacial acetic acid]]) is added. This kills the cells and hardens the nuclei of the remaining white blood cells. The cells are generally fixed repeatedly to remove any debris or remaining red blood cells. The cell suspension is then dropped onto specimen slides. After aging the slides in an oven or waiting a few days they are ready for banding and analysis.