Comparison of direct harvest and cultures for karyotyping EDTA anticoagulated marrow.

Studies were undertaken to determine whether EDTA was a satisfactory anticoagulant for tissue specimens for cytogenetic analysis and to investigate a modification of a currently used culture technique for obtaining metaphases. The latter involved to prolonged exposure to very low-dose colcemid and was successful in qualitative or quantitative enhancement, or both, of the temperature yield over that obtained from direct harvest in 53% of the patients studied. EDTA is a suitable anticoagulant for cytogenetic studies of specimens from either direct harvest or short-term culture if the specimen is either processed within 24 hr after collection or diluted 1:1 with Eagles minimal essential media, supplemented with fetal bovine serum and refrigerated until processed. Success has been obtained with specimens stored up to 144 hr.