Figure 1

Distribution of length and GC content of non-coding DNA in T. parva. Histograms of intergenic region length (A) and intron length (B), and GC content (%) of intergenic regions (C) and introns (D). The length of intergenic regions fits a lognormal distribution (A), while GC content of both types of non-coding DNA is normally distributed (C, D). The histogram of intron length is biomodal, which probably results from the overlay of two independent distributions of small (mode = 55) and large (mode = 80) introns, much like what had been documented for other organism [19]. Similar results are found in T. annulata (not shown).