FISH unveils a unified method for multi-marker biodose assessment

Area of Science:

• Radiation Biology
• Cytogenetics
• Biomolecular Imaging

Background:

• Accurate radiation dose assessment is critical for medical response after radiation incidents.
• Current methods for quantifying cytogenetic biomarkers (dicentrics, translocations, fragments) are often inefficient and inconsistent.
• There is a need for improved biodosimetry tools for both recent and past radiation exposures.

Purpose of the Study:

• To develop and validate a single fluorescence in situ hybridization (FISH) method for quantifying multiple cytogenetic biomarkers simultaneously.
• To enhance the accuracy and efficiency of radiation dose estimation in biodosimetry.
• To provide a more reliable tool for assessing radiation exposure in various scenarios.

Main Methods:

• Developed a unified FISH technique to detect dicentrics, balanced/unbalanced translocations, and acentric fragments in the same metaphase.
• Generated independent calibration curves for each marker.
• Validated the method using five blinded samples, comparing results with standard cytogenetic methods and protein biomarkers (γH2AX, 53BP1).

Main Results:

• The multimarker FISH approach enabled precise dose estimation from a single sample, minimizing interexperimental variation.
• Calibration curves allowed for dose estimation with smaller class intervals, adhering to IAEA and ISO guidelines.
• Validation showed the multimarker approach yielded the closest dose estimates (2-7% variation) compared to other cytogenetic techniques.

Conclusions:

• The unified FISH-based approach offers enhanced precision for radiation dose estimation.
• This method provides a more reliable and accurate tool for diverse biodosimetry applications, including recent and past exposures.
• Simultaneous quantification of multiple cytogenetic markers improves overall accuracy and efficiency in radiation biodosimetry.