Assessment of in vivo chemical mutagenesis by long-read sequencing.

Evaluating the mutagenic properties of chemicals is crucial for understanding their potential cancer risks. Recent Illumina-based error-corrected sequencing techniques have enabled the direct detection of mutations induced de novo by mutagens. However, as the Illumina platform lacks intrinsic error-correction capabilities, complex library preparations and bioinformatic processes are necessary to identify these rare mutations. In this study, we evaluated whether long-read PacBio-based HiFi sequencing (HiFi seq), which has integrated error-correction, can detect de novo mutations induced by mutagens in C57BL/6 mouse tissues. Using HiFi seq, dose-dependent increases in mutation frequencies were found in tissues from mice exposed to 7,12-dimethylbenz[a]anthracene, procarbazine, and N-propyl-N-nitrosourea. Furthermore, the mutational signatures derived from these exposures were consistent with those previously reported for these mutagens. This study demonstrates that HiFi seq can complement established mutation detection assays to facilitate the identification of hazardous compounds.