Revision of the chromosome anomalies of the T-cell malignant cell line peer.

A high resolution chromosome banding method was applied to define the karyotype of the PEER cell line. It was found significantly different from that previously described, and can be characterized as follows: 46,XX,-4, del(5) (q21q23), del(6)(q14q22), del(9)(p12p21), i(9p), +der(4) rea(4) involving a large duplication of 4q. The cell cycle duration varies in relation to the time after splitting, slow from 0 to 48 h and faster from 48 to 96 h. The average time found was 25 h with durations of 6 and 15 h for G2 and S-phases, respectively. This variable cell cycle led us to change the conditions of BrdU incorporation to obtain a convenient R-banding. According to our own experience, this can be transposed to many other malignant cells to obtain a high resolution chromosome banding.