Article 2 animal tissue 2 controlled study ethylnitrosourea 2 female 2 male 2 nonhuman 2 nucleic acid base substitution 2 point mutation 2 whole genome sequencing 2 DNA extraction 1 Germline mutation 1 Mutation frequency 1 Spi− assay 1 Whole genome sequencing 1 animal cell 1 animal experiment 1 benzo[a]pyrene 1 body weight gain 1 body weight loss 1 bone marrow 1 chromosome 1 1 de novo mutation 1 exome 1 gene function 1 genome 1 genomic DNA 1 germ cell 1 germline mutation 1 gpt assay 1