Composition of the toxic and nontoxic genotype in populations of Planktothrix across Europe. Allelic discrimination plot of toxic and nontoxic Planktothrix genotypes of populations differing in pigmentation as determined by a custom TaqMan SNP genotyping assay within mcyT, indicative of a genotype that lost (allele 1) or still contains (allele 2) the mcy gene cluster. Delta Rn values represent the difference in fluorescence from the post-PCR and pre-PCR reads of the normalized reporter (VIC, FAM). The symbols represent the mean ± SE of measurements in triplicate. When not visible, the error bars are hidden behind the symbol. Values located close to the no-template control failed to amplify.