FISH unveils a unified method for multi-marker biodose assessment.

Accurate dose assessment following radiation disasters or accidents is crucial for informed medical interventions. Cytogenetic biomarkers, such as dicentrics (dic), translocations, and chromosomal fragments, are essential for radiation biodosimetry in various exposure scenarios. However, quantifying these markers via separate staining and detection methods presents challenges in terms of efficiency and consistency. This study aimed to quantify multiple cytogenetic markers, including dic, balanced and unbalanced translocations and acentric fragments, from the same metaphases via fluorescence in situ hybridization (FISH). By enabling multimarker dose estimation from a single sample, this approach minimizes interexperimental variation and improves overall accuracy. Independent calibration curves were generated for each marker, enabling precise dose estimation with smaller class intervals, in accordance with the IAEA and ISO guidelines. The method was validated by estimating doses for five blinded samples via both standard cytogenetic methods and protein biomarkers (γH2AX and 53BP1). The multimarker approach yielded the closest estimates with 2-7% variation from true doses, providing the most accurate results among all cytogenetic techniques. This unified FISH-based approach enhances the precision of dose estimation for both recent and past radiation exposures, offering a more reliable tool for diverse biodosimetry applications.