Abstract
A specificity of biological effects with high LET-ionizing radiation like heavy ion particles would be based on the more condensed physical events with the extremely localized dose deposition. The most typical damage is the double strand break (DSB) among various resulting from multiple localized lesions termed clustered DNA damage. There are many studies indicating increase of DSB with increasing LET. However, there are also equal numbers of studies showing the inverse correlation between LET and DSB yields. This inconsistency for the relationship between LET and DSB has been still one of big questions of radiation biology to elucidate the molecular mechanisms of radiobiological effect. The discrepancy suggests the existence of undefined factors for determining the detectable yields of DSB for LET, including used radiations, target molecules (damage), and analyzing procedure etc. In this workshop, we would offer a brief review summarizing the previous and recent data for this matter, and discuss whether DSB increases or decreases with increasing LET.
