Biomarkers specific to densely-ionising (high LET) radiations.

Area of Science:

• Radiation Biology
• Genetics
• Epidemiology

Background:

• High-energy radiation exposure requires reliable biomarkers for epidemiological studies.
• Current biomarkers may lack specificity for densely-ionizing radiations like alpha particles or neutrons.

Purpose of the Study:

• To introduce and evaluate the H value as a specific biomarker for high-linear energy transfer (LET) radiation exposure.
• To compare the discriminatory power of the H value against the previously suggested F value.

Main Methods:

• The H value is defined as the ratio of induced inter-chromosomal aberrations to intra-arm aberrations.
• Theoretical and experimental studies were used to assess the H value's potential.
• In vitro studies confirmed the approach for unstable aberrations.

Main Results:

• The H value is theoretically and experimentally suggested to differ by a factor of three between high-LET radiation and other clastogens.
• The H value shows greater discrimination potential than the F value.
• Chromosomal biomarkers, including the H value, demonstrate long-term stability and measurability post-exposure.

Conclusions:

• The H value is a practical and stable biomarker for high-LET radiation exposure.
• This biomarker can enhance epidemiological studies of individuals exposed to alpha particles or neutrons.
• Ongoing studies are testing the H value in Russian radiation workers with documented high- or low-LET exposures.