Accurate gene expression-based biodosimetry using a minimal set of human gene transcripts

Area of Science:

• Radiation Biology
• Molecular Biology
• Genomics

Background:

• Biological dosimetry is crucial for assessing radiation exposure after nuclear events.
• Conventional methods are slow, costly, and not portable for mass casualty triage.

Purpose of the Study:

• To develop a rapid, cost-effective, and portable biological dosimetry method using gene expression.
• To assess the feasibility of polymerase chain reaction (PCR) for biodosimetry in mass casualty scenarios.

Main Methods:

• Exposed human blood samples to cobalt-60 gamma radiation (0-10 Gy).
• Measured mRNA expression of 121 genes using reverse-transcription real-time PCR at multiple time points.
• Utilized stepwise regression to identify key gene transcripts for dose prediction.

Main Results:

• A model using 3-4 gene transcripts (ASTN2, CDKN1A, GDF15, ATM) explained ≥0.87 of dose variance.
• Achieved high sensitivity and specificity (0.98) using receiver-operator characteristics.
• Accurate dose prediction up to 6 Gy, with saturation effects at higher doses.

Conclusions:

• Gene transcript analysis via PCR provides accurate and rapid biological dosimetry.
• This method is suitable for mass casualty triage and clinical radiation emergencies.
• Potential for development into a field-portable device for radiation exposure assessment.