Pattern of SNP frequency. A. The graphs illustrate the relationship between counts and coverage for the surveyed positions in the four tested libraries. Approximately half the number of reads were obtained from the control (C) and T1 libraries as for the C2 and C3 (Table 3). B. The absolute SNP count is shown for the tested individuals, using four bars listed in the order (C, T1, T2, T3) for each change type. Mutagenized individuals (T1, T2, T3) display increased SNP types consistent with the mutagen action (GC > AT) while the untreated individual (the first bar of each group) displays only background changes in both de novo referenced and O.s. genome referenced analyses. Changes that differ statistically from the expectation of random sequencing errors are marked by the asterisk.