Histograms of transition substitutions from the reference genomic DNA to full-length cDNA. Only transitions, whose frequencies are generally threefold to fourfold higher than transversions, are shown. (A) Total number of transition substitutions in 128,406 cDNAs (total of 254,330,565 bases). (B) Number of cDNAs with a significantly increased likelihood of specific substitutions, as determined by our scan statistic method (see Methods). There is a population of transcripts with excessive A-to-G substitutions that are not apparent in other transitions. A-to-G substitution: 2674 significant transcripts; G-to-A substitution: 35 significant transcripts; T-to-C substitution: 36 significant transcripts; C-to-T substitution: 52 significant transcripts.
