(A–C) The distances (in nucleotides) between dnAUGs and annAUGs in downPeptide genes are graphed for all frames pooled (A) or partitioned by frame (C). Compared to the frequencies of all dnAUGs within 100 nt of the annAUG in the full genome (B), frame 1 downPeptides are over-represented (chi-square p < 0.001, all bins > 10). (D) The lengths of frame-2 or -3 ORFs, defined by dnAUGs of detected downPeptides (188 ORFs, mean 74 nt), are compared with the full set of theoretical ORFs of frame-2 or -3 dnAUGs that start and finish within the annotated frame-1 ORFs (86,088 ORFs, mean 60 nt). ORFs of detected downPeptides are significantly longer based on chi-squre analysis of the full distributions (chi-square p < 2*10−7), as well as bootstrap analysis of means (p < 0.002).