Mapping chromosomal breakpoints of Burkitt's t(8;14) translocations far upstream of c-myc.
To analyze the region upstream of c-myc, a number of novel probes were established. These were generated by chromosomal walking starting from the breakpoint of the chromosomal translocation of the B-cell line 380 and by cloning the breakpoint of the translocation of the Burkitt lymphoma cell line IARC/BL72. Using the newly isolated probes a detailed physical map of 500 kilobases of the region upstream of c-myc was established applying pulsed-field gel electrophoresis. The chromosomal breakpoint of IARC/BL72 cells was mapped to a site 55 kilobases 5' of c-myc. A region 20 kilobases in length and containing the breakpoints of 380, EW36, P3HR-1, and Daudi cells was identified 170-190 kilobases upstream of c-myc. In addition the HPV18 integration site in HeLa cells was located between 340 and 500 kilobases 5' of c-myc. The probes were used to define the c-myc amplification units in Colo320-HSR and HL60 cells as well as in four cases of small cell lung cancer. Evidence is provided that the amplicon of HL60 cells is discontinuously organized.
Joos
S
S
GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Klinische Molekularbiologie und Tumorgenetik, Munich, Germany.
Haluska
F G
FG
Falk
M H
MH
Henglein
B
B
Hameister
H
H
Croce
C M
CM
Bornkamm
G W
GW
D001483:Base Sequence; D002051:Burkitt Lymphoma / Q000235:genetics*; D018288:Carcinoma, Small Cell / Q000235:genetics; D016386:Chromosome Walking / Q000379:methods*; D002883:Chromosomes, Human, Pair 14; D002898:Chromosomes, Human, Pair 8; D016521:Electrophoresis, Gel, Pulsed-Field; D005784:Gene Amplification; D016259:Genes, myc / Q000235:genetics*; D015698:Genomic Library; D006801:Humans; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional / Q000235:genetics*; D014178:Translocation, Genetic / Q000235:genetics*; D014407:Tumor Cells, Cultured