Abstract: | We report a micromethod for chromosome preparation from individual hematopoietic colonies cultured in methylcellulose. The entire process was carried out on poly-Lysine (PL)-coated slides. Individual colonies were transferred into 10 microliter of 0.075 M KCl and placed on PL-coated slides. After hypotonic treatment of the colony cells and their attachment to the slides, the cells were fixed by a three-step procedure as follows: addition of a 30% fixative (3:1 methanol:acetic acid) diluted with the hypotonic solution, addition of 20% ethanol, and subsequent immersion of the slides in a 100% fixative. The slides were flame dried and Giemsa stained. Q- and G-banding techniques also were used. These procedures provided analyzable chromosome preparations, even from colonies containing fewer than 50 cells. |