The characterization of high-resolution G-banded chromosomes of man

Abstract

The detailed characterization of G-banding patterns of high resolution human chromosomes has been possible with the utilization of a refined cell synchronization technique which routinely yields a large number of excellent quality cells in late prophase, prometaphase, early metaphase, and mid-metaphase. The mitotic cells exhibit up to a 400% increase in the number of bands previously visualized by standard methods. From studies of the banding patterns, it has become evident that the G-positive and, to some extent, the G-negative bands of mid-metaphase results from a coalescence of finer subbands of earlier stages and that each band and its corresponding subbands maintain a constant location throughout the process of chromosome condensation. A precise schematic representation of the number, position, height and staining intensity of bands is presented for the five largest chromosomes of the complement at the four mitotic stages.

High-resolution chromosome R-banding in lymphoblastoid cell lines by the combined use of cell synchronization and ethidium bromide treatment

“…2 were still around 3%. These figures are considerably better than those achieved by aphidicolin-induced synchronization of LCLs (Kuwano and Kajii, 1991), and are even well comparable with data for peripheral blood lymphocyte cultures subjected to MTX or TdR synchronization (Yunis et al, 1978;Drouin et al, 1988;RCnne, 1992).…”

“…1). It is noteworthy that this timing was considerably delayed in comparison with standard peripheral blood cultures, where the mitotic peak usually occurs 4.5 to 5 hr after release from the S phase block (Yunis et al, 1978;Drouin et al, 1988). Another finding was that the maximum mitotic indices of TdR-synchronized cell cultures were generally higher (3-4%) than those of MTX-treated cells (2-2.5%).…”

“…One involves cell synchronization at the S-phase using agents such as methotrexate (MTX), excess thymidine (TdR), or 5-bromodeoxyuridine (BrdU), with subsequent release from the block (cf, Yunis et al, 1978;Rcnne, 1992), and the other involves the application of DNA-binding agents, such as ethidium bromide (EB), that inhibit mitotic chromosome condensation (of, Ikeuchi, 1984). These techniques have been essentially devised for and employed in human peripheral T-lymphocyte cultures with phytohemagglutinin (PHA), and they cannot necessarily be applied to other cell culture systems.…”

Provisional Mapping of the Gene for a Cell Surface Marker, GA-l, in the Red-necked Wallaby Macropus rufogriseus

“…Chromosomes were C-banded using the method of Sumner (1972) and G-banded according to the methods of Seabright (l97!) and Yunis et al (1978). For each chromosome preparation, 50 C-and/or 50 G-banded metaphase spreads were analysed for chromosomal content.…”

9‐Aminoacridine: An efficient reagent to improve human and plant chromosome banding patterns and to standardize chromosome image analysis

“…The necessary degree of chromosome contraction is usually achieved by different approaches: cell synchronization by amethopterin (1)(2)(3), by hydroxyurea or aphidicolin (4), or by thymidine or bromodeoxyuridine (5-7); different concentrations of contractile agents such as colchicine and colcemide (8 -15); and DNA intercalating agents (ethidium bromide, acridine orange) that interfere in the process of chromosome condensation (8,(15)(16)(17)(18)(19). To achieve the necessary degree of chromosome contraction, combinations of these methods are sometimes used (16,20).…”