Sequence annotation changes since 1996. Arrow symbol represents the location of an indel [inserted or deleted nucleotide(s)]. Only the most common types of change have been diagrammed. (A) New ORF addition: 523 small ORFs have been added as a result of new experimental reports, comparative genomic analysis and sequence changes. (B) 5′ Extension: 64 ORFs were extended when an indel caused an upstream ATG to be brought in frame with the existing coding region; 21 extensions resulted from the discovery of an upstream intron. (C) 3′ Extension: 51 ORFs were extended when the sequence of the ORF changed to alter the reading frame and/or STOP codon position. Note that sequence changes also produced 20 ORFs with 3′ deletions (not diagrammed). An additional four 3′ extensions resulted from the discovery of a downstream intron (not diagrammed). (D) 5′ Deletion: 113 ORFs have decreased in length as a result of comparative analysis or because experimental results showed that the first ATG was not the start of translation. (E) Merger: 20 sequence changes have merged two adjacent ORFs

Changes per chromosome since 1996. For each chromosome, yellow indicates the number of new ORFs; red indicates the number of ORFs revised due to changes in the chromosomal sequence; and blue indicates the number of ORFs that were revised without changes to the chromosomal sequence. Sequence changes include confirmed changes reported by the research community (Schmalix and Bandlow, 1994; Xiao et al., 1998; Treton et al., 2000; Angus-Hill et al., 2001; Beh et al., 2001; Kaliraman et al., 2001; Moukadiri and Zueco, 2001; Palmer et al., 2001; Robben et al., 2002; Jaspersen et al., 2002; Denis and Cyert, 2002; Muller et al., 2003; Charlie Boone, personal communication; Jim Brown, personal communication; Clyde Denis, personal communication; Tim Formosa, personal communication; Claude Gaillardin and Aaron P. Mitchell, personal communication; Gerard Manning, personal communication). Note that the graph includes only changes that were incorporated into the reference genome. A total of 43 proposed sequence changes have been rejected because re-sequencing verified the original sequence. An additional 54 proposed annotation-based revisions have also been rejected due to inadequate data