title: Comparison of prometaphase chromosome techniques with emphasis on the role of colcemid.
abstract: Six different techniques were evaluated to define better those technical factors that are most critical for obtaining prometaphase cells for banding analysis. Our results demonstrate: colcemid exposures of 30 min or less have no effect on increasing the yield of prometaphase cells, colcemid exposures of greater than 0.1 microgram/ml can be toxic, methotrexate depresses the mitotic index significantly and seems to increase the incidence of prometaphase cells only because it suppresses later forms; and (d) the optimum number of cytogenetically satisfactory prometaphase cells can be obtained with a 4-h exposure to a combination of low concentration actinomycin D (0.5 microgram/ml) and colcemid (0.1 microgram/ml). This technique inhibits chromosome condensation while permitting prometaphase cells to accumulate for 4 h.
mesh_terms: D002869:Chromosome Aberrations; D002871:Chromosome Banding / Q000379:methods*; D003609:Dactinomycin / Q000494:pharmacology; D003703:Demecolcine / Q000494:pharmacology*; D004996:Ethidium / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008727:Methotrexate / Q000494:pharmacology; D008940:Mitotic Index; D011418:Prophase / Q000187:drug effects
chemical_list: D003609:Dactinomycin; D004996:Ethidium; D008727:Methotrexate; D003703:Demecolcine