{ * Smarty * } Wheat Genome Annotation
 
 

Genome Facts

The cereal known as wheat comes from several closely related species. Four of these species are cultivated: einkorn (Triticum monococcum ssp. monococcum), emmer (T. turgidum ssp. durum), timopheevii (T. timopheevii ssp. timopheevii) and common or bread wheat (T. aestivum).

Common/bread wheat(Triticum aestivum) is a disomic allohexaploid (AABBDD genomes). It arose from the convergence of three diploid ancestors that have diverged from a common ancestor and coevolved some 2.5 to 4.5 million years ago. Approximately 0.5 million years ago, the diploid wheats T. urartu (AA genomes) and Aegilops speltoides (SS genomes, most closely related to the B genome) hybridized to form the tetraploid wheat T. turgidum (AABB), which includes durum wheat. About 8,000 years ago T. turgidum hybridized with the wild diploid goatgrass Aegilops tauschii (DD genomes) to form bread wheat. Mapping studies using cDNAs and ESTs as RFLP probes indicate that the three genomes of hexaploid wheat carry, in general, the same genes at the same relative positions along homoeologous chromosomes, aside from a few well-known large translocations, and probably many other still unknown local rearrangements.

Wheat nucleotide sequences in GenBank

GenBank division

Entries

Total bp

dbEST

880,515

339,239,649

dbGSS

32,581

6,271,668

dbHTG

80

1,552,156

dbPLN

7,843

10,035,245

dbSTS

658

311,744

WGS

5,055

3,691,256

Total

926,732

361,101,718


Wheat related publications in PubMed

Publications in PubMed...

Total

...with wheat in title

9,256

...with wheat in abstract

23,116


TIGR Annotated Genes

Wheat Gene Features

Total

Total BAC number

67

Total gene models

582

Average gene size (bp)

2,220

Average exon number

2.8

Average exon length (bp)

318

Average exon GC content (%)

55.9

Average intron number

1.8

Average intron length (bp)

694

Average intron GC content (%)

43.9


Genes from TIGR Annotated Wheat BACs

Gene number

Percentage

Ave. gene size (bp)

Known/Putative

190

32.6

2721

Expressed

25

4.3

3368

Conserved Hypothetical

32

5.5

1871

Hypothetical

335

57.6

1884

 
 
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