Figure 5. A representative Lineage 2 strain acquires isoniazid and ethambutol resistance at a higher rate.

Fluctuation analysis was used to determine the isoniazid (1μg/mL) and ethambutol (5μg/mL) resistance rate for the Lineage 4 strain, CDC1551, (shown in red) and the Lineage 2 strain, HN878 (shown in blue). Circles represent mutation frequency (number of mutants per cell in a single culture), where darker circles represent multiple cultures with the same frequency. Bars represent the estimated mutation rate, with error bars representing the 95% confidence interval. Significance was determined by non-overlapping 95% confidence interval. Values are listed in Supplementary Table 1.