The effects of Atm haploinsufficiency on mutation rate in the mouse germline and somatic tissue

Using single-molecule PCR, the frequency of spontaneous and radiation-induced mutation at an expanded simple tandem repeat (ESTR) locus was studied in DNA samples extracted from sperm and bone marrow of Atm knock-out (Atm+/-) heterozygous male mice. The frequency of spontaneous mutation in sperm and bone marrow in Atm+/- males did not significantly differ from that in wild-type BALB/c mice. Acute exposure to 1 Gy of γ-rays did not affect ESTR mutation frequency in bone marrow and resulted in similar increases in sperm samples taken from Atm+/- and BALB/c males. Taken together, these results suggest that the Atm haploinsufficiency analysed in our study does not affect spontaneous and radiation-induced ESTR mutation frequency in mice.