Microsatellite analysis for determination of the mutagenicity of extremely low-frequency electromagnetic fields and ionising radiation in vitro.
Extremely low-frequency electromagnetic fields (ELF-EMF) have been reported to induce lesions in DNA and to enhance the mutagenicity of ionising radiation. However, the significance of these findings is uncertain because the determination of the carcinogenic potential of EMFs has largely been based on investigations of large chromosomal aberrations. Using a more sensitive method of detecting DNA damage involving microsatellite sequences, we observed that exposure of UVW human glioma cells to ELF-EMF alone at a field strength of 1 mT (50 Hz) for 12 h gave rise to 0.011 mutations/locus/cell. This was equivalent to a 3.75-fold increase in mutation induction compared with unexposed controls. Furthermore, ELF-EMF increased the mutagenic capacity of 0.3 and 3 Gy gamma-irradiation by factors of 2.6 and 2.75, respectively. These results suggest not only that ELF-EMF is mutagenic as a single agent but also that it can potentiate the mutagenicity of ionising radiation. Treatment with 0.3 Gy induced more than 10 times more mutations per unit dose than irradiation with 3 Gy, indicating hypermutability at low dose.
Mairs
Robert J
RJ
Targeted Therapy Group, Division of Cancer Science and Molecular Pathology, Glasgow University, Cancer Research UK Beatson Laboratories, and Department of Child Health, Yorkhill Hospital, Glasgow, UK. r.mairs@beatson.gla.ac.uk
Hughes
Kate
K
Fitzsimmons
Sara
S
Prise
Kevin M
KM
Livingstone
Anne
A
Wilson
Lesley
L
Baig
Nazia
N
Clark
Anne Marie
AM
Timpson
Alan
A
Patel
Gaurang
G
Folkard
M
M
Angerson
Wilson J
WJ
Boyd
Marie
M
D001483:Base Sequence; D045744:Cell Line, Tumor; D004249:DNA Damage; D017931:DNA Primers; D004574:Electromagnetic Fields; D006801:Humans; D018895:Microsatellite Repeats / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011839:Radiation, Ionizing; D012680:Sensitivity and Specificity
D017931:DNA Primers