Table 1

Comparison of Release 2 and 3 genome statistics

Description*
Release 2 (% of total)
Release 3 euchromatin(% of total)

Total protein-coding genes
13,474
13,379
Total length of euchromatin
116.2 Mb
116.8 Mb
Exons
54,793
60,897
Protein-coding exons
50,667
54,934
Length of genome in exons
23.3 Mb (20%)
27.8 Mb (24%)
Introns
41,381
48,257
Genes with 5' UTR
7,680 (57%)
10,227 (76%)
Transcripts with 5' UTR
8,499 (59%)
14,707 (81%)
Average 5' UTR length
204 nucleotides
265 nucleotides
Genes with 3' UTR
4,824 (36%)
9,646 (72%)
Transcripts with 3' UTR
5,381 (38%)
14,012 (77%)
Average 3' UTR length
370 nucleotides
442 nucleotides
Average ratio of length of CDS/transcript§
0.86
0.75
Total protein-coding transcripts
14,335
18,106
Genes with alternative transcripts
689 (5%)
2,729 (20%)
Average number of transcripts per alternatively spliced gene
2.25
2.75
Total number alternative transcripts
861
4,743
Number of introns contained in 5'UTRs
2,977
6,787
Number of introns contained in 3' UTRs
1,004
1,088
Unique peptides
13,922
15,848
Unique peptides unchanged from R2 to R3
8,769 (63%)
8,769 (55%)
Genes deleted from R2 to R3
345
NA
New protein-coding genes in R3
NA
802

*Abbreviations: UTR, untranslated region; CDS, (protein)-coding sequence; R2, Release 2; R3, Release 3; NA, not applicable. All statistics are for protein-coding genes only. Based on the annotation of protein-coding genes in the euchromatin (long chromosome arms); another 297 protein-coding genes are annotated in the heterochromatin (non-redundant WGS3 [25]). In this and Tables 2,3,4, the numbers are based on a version of the annotation database frozen on November 25, 2002. Any exon containing CDS, even if the majority of the exon is UTR. §The length of the coding region divided by the length of the entire protein-coding transcript, averaged over all protein-coding transcripts. Determined because many alternative transcripts encoded the identical CDS and differed only in the UTR.

Misra et al. Genome Biology 2002 3:research0083.1   doi:10.1186/gb-2002-3-12-research0083