#IN5D NUMBER SEQUENCES SERIAL#

In the case of bread wheat, the International Wheat Genome Sequencing Consortium (IWGSC) has developed a roadmap for sequencing projects, using flow sorting techniques to isolate individual chromosomes and chromosome arms. Over the last few years, through the development of high-throughput next generation sequencing (NGS) technologies, the sequencing of very large genomes has become increasingly feasible however, the assembly of these sequence reads particularly from the highly repetitive regions remains challenging. Therefore, many genetic features have 3 homoeologous variants, some of which may not be functional.

#IN5D NUMBER SEQUENCES SERIAL#

aestivum is an allohexaploid derived from serial hybridization events between three different diploid wheat ancestors with A, B and D genomes, resulting in each of its 7 chromosomes being present in 3 phylogenetically related but divergent sub-genomes (2n = 6× = 42, genome formula AABBDD). However, its very large (~17 Gb), polyploid and repetitive genome presents major challenges to genome sequencing. ERP002330īread wheat ( Triticum aestivum L.) is among the world’s most important crops, occupying 17% of all cultivated land and supplying about 55% of carbohydrates for human consumption. Sequence accessionsĮBI European Nucleotide Archive, Study no. Although our data support the large-scale conservation of Triticeae chromosome structure, they also suggest that some regions are evolving rapidly through frequent gene duplications and translocations. The virtual gene order revealed a large-scale chromosomal rearrangement in the peri-centromeric region of 5DL, and a concentration of non-syntenic genes in the telomeric region of 5DS. The order of conserved genes in syntenic regions of previously sequenced grass genomes were integrated with physical and genetic map positions of 518 wheat markers to establish a virtual gene order for chromosome 5D. By a combination of sequence similarity and assembly-based methods, ~74% of the sequence reads were classified as repetitive elements, and coding sequence models of 1314 (5DS) and 2975 (5DL) genes were generated. We generated shotgun sequences from each arm of flow-sorted Triticum aestivum chromosome 5D using 454 FLX Titanium technology, giving 1.34× and 1.61× coverage of the short (5DS) and long (5DL) arms of the chromosome respectively. Elucidating its sequence and structure will therefore facilitate wheat breeding and crop improvement. In particular, the D sub-genome is relatively lacking in genetic diversity, making it both difficult to map genetically, and a target for introgression of agriculturally useful traits. The ~17 Gb hexaploid bread wheat genome is a high priority and a major technical challenge for genomic studies.

In5d number sequences