Resistance to pyrimethamine is correlated with resistance to cycloguanil.

<p>(A) Correlations between the IC₅₀ values for pyrimethamine (<i>y</i>-axis) and cylcoguanil (<i>x</i>-axis). Each point corresponds to a single genotype in the landscape. The landscapes are significantly correlated for both traits, indicating cross-resistance (IC₅₀: <i>R</i>² = 0.74, <i>P</i> = 3.9 X 10⁻⁵; Error bars on IC₅₀ values represent standard errors of the published experimental replicates [<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004710#pcbi.1004710.ref011" target="_blank">11</a>,<a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004710#pcbi.1004710.ref012" target="_blank">12</a>]. (B) A graph of the <i>R</i>² as a function of drug concentration, demonstrating that the landscapes remain correlated across drug concentrations, albeit less so as drug concentration increases. Pearson product-moment correlations were significant (<i>P</i> < 0.05) at all concentrations except the highest in our study (1.0 X 10⁵ uM), which was nearly significant (<i>P</i> = 0.067). Individual scatter plots that produce these <i>R</i>² values, and corresponding <i>P</i> values, can be found in <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1004710#pcbi.1004710.s001" target="_blank">S1 Fig</a>.