Effects of electron-beam irradiation on buccal-cell DNA

Abstract

Buccal cells were collected from 29 participants, by use of mouthwash rinses, and were split into equal aliquots, with one aliquot irradiated by electron-beam (E-beam) irradiation equivalent to the sterilizing dosage used by the U.S. Postal Service and the other left untreated. Aliquots were extracted and tested for DNA yields (e.g., TaqMan assay for quantifying human genomic DNA), genomic integrity, and amplification-based analysis of genetic variants (e.g., single-nucleotide polymorphisms [SNPs] and single tandem repeats [STRs]). Irradiated aliquots had lower median DNA yields (3.7 μg/aliquot) than untreated aliquots (7.6 μg/aliquot) (P < .0005) and were more likely to have smaller maximum DNA fragment size, on the basis of genomic integrity gels, than untreated aliquots (P < .0005). Irradiated aliquots showed poorer PCR amplification of a 989-bp β-globin target (97% for weak amplification and 3% for no amplification) than untreated aliquots (7% for weak amplification and 0% for no amplification) (P 989 bp) or require whole-genome amplification may be compromised.