Chromosomal mapping of proviral sequences by FISH.

FISH analysis using SF1m vector plasmid DNA as probe and subsequently performed M-FISH was established to detect proviral inserts in SF1m-transduced HT1080 cell line clones. (A-B) M-FISH karyogram and metaphase spread of HT1080 clone N3 presenting a near tetraploid karyotype (n = 87) with following recurrent chromosomal aberrations: dup(5p), t(4;8), t(3;11), i(13q), and i(18p). (C) Same metaphase spread after FISH using the SF1m vector plasmid DNA probe shows hybridization signals on the human wild-type MDR1 gene locus 7q21 and on chromosome 1q41. (D-F) Chromosomal localization of the SF1m vector plasmid DNA probe in HT1080 cell line clones N2 (12q14), N3 (1q41), and N4 (20q11), respectively. Additional signals are present on the human wild-type MDR1 gene locus (7q21).