Biological effects of carbon ion beams with various LETs on budding yeast Saccharomyces cerevisiae

Highlights: • Analysis of survival rates associated with different levels of radiation revealed that the survival rate decreased with increasing LET, while the frequency of mutations increased. • The mutation rate increased consistently with LET, indicating that a high LET ion beam is more mutagenic than its low LET ion counterpart. • Yeast rad52 mutant strain is more radiosensitive to killing than yeast cells rad50 strain. - Abstract: It has been established that irradiation with higher linear energy transfer (LET) increases lethality and mutagenicity more than that with lower LET. However, the characteristics specific to carbon ion beam have not yet been elucidated. Yeast cells were irradiated with carbon ions with an LET of 13 or 50 keV/μm, and cell survival and mutation frequency were analyzed. The results, combined with our previous findings for ions with an LET of 107 keV/μm, demonstrated that, in conjunction with an increase in LET, cell survival decreased, while mutation frequency increased. This indicates that a carbon ion beam with a higher LET is more mutagenic than one with a lower LET.