Different mutational function of low‐ and high‐linear energy transfer heavy‐ion irradiation demonstrated by whole‐genome resequencing of Arabidopsis mutants

Summary Heavy‐ion irradiation is a powerful mutagen that possesses high linear energy transfer (LET). Several studies have indicated that the value of LET affects DNA lesion formation in several ways, including the efficiency and the density of double‐stranded break induction along the particle path. We assumed that the mutation type can be altered by selecting an appropriate LET value. Here, we quantitatively demonstrate differences in the mutation type induced by irradiation with two representative ions, Ar ions (LET: 290 keV μm−1) and C ions (LET: 30.0 keV μm−1), by whole‐genome resequencing of the Arabidopsis mutants produced by these irradiations. Ar ions caused chromosomal rearrangements or large deletions (≥100 bp) more frequently than C ions, with 10.2 and 2.3 per mutant genome under Ar‐ and C‐ion irradiation, respectively. Conversely, C ions induced more single‐base substitutions and small indels (