Minisatellite and HPRT mutations in V79 and human cells irradiated with gamma rays.
The induction of mutations at the Hprt locus and minisatellite sequences was studied in V79 cells, peripheral blood lymphocytes (PBL) and lymphoblastoid cells (CCRF-CEM) exposed to gamma rays. In V79 cells the Hprt mutant frequency increased with dose at least up to 6.0 Gy, whereas the number of HPRT mutant lymphocytes increased up to 3 Gy. Clones derived from single irradiated cells were screened for mutations at minisatellite sequences by DNA fingerprint analysis. In V79 cells, a dose-response curve for minisatellite alterations was obtained up to 4.5 Gy. In contrast, very few mutations at minisatellite sequences (2/137) were detected among clones isolated from PBL of two donors irradiated with 1-4 Gy. Similar results were observed in lymphoblastoid CCRF-CEM cells irradiated with 2-3 Gy (4 mutants/180 clones), suggesting that in human lymphoid cells minisatellite DNA is more stable than in other mammalian and human cell lines.
INFN, Laboratori Nazionali di Legnaro, Padova, Italy.
S
S
Canova
M
M
Perin
M
M
Mognato
S
S
Favaretto
R
R
Cherubini
L
L
Celotti
D000818:Animals; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D003412:Cricetulus; D016172:DNA Fingerprinting / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D005787:Gene Frequency; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics*; D018598:Minisatellite Repeats / Q000528:radiation effects*; D009154:Mutation
D007041:Hypoxanthine Phosphoribosyltransferase