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Chromosome 4A 454 Survey Sequencing

Targeted chromosomes

Click on a chromosome to access associated data (when available) at URGI Sequences Repository.

Project team

First nameLast nameEmailInstitutionCountry
Jaroslav Dolezel dolezelSPAMFILTER@ueb.cas.cz IEB Czech Republic
Miroslav Valárik valarikSPAMFILTER@ueb.cas.cz IEB Czech Republic

Project collaborators

First nameLast nameEmailInstitutionCountry
Klaus Mayer K.mayerSPAMFILTER@helmholtz-muenchen.de MIPS Germany

Project funding

Funding for the 454 survey sequence is provided by the Spanish Ministry of Science and Technology (MICINN), and the Institute of Experimental Botany in the Czech Republic. Funding for the Illumina survey sequence and assembly is being provided by the sponsors of the IWGSC survey sequence initiative.


In this project, mitotic chromosome flow sorting was used to separately purify and then shotgun-sequence a pair of telocentric chromosomes that together form chromosome 4A (856 Mb/1C) of wheat. Roche 454 sequence reads representing approximately 2.2x coverage of 4AL and 1.7x coverage of 4AS were generated. The isolation of this much reduced template and the consequent avoidance of the problem of sequence duplication, in conjunction with synteny-based comparisons with other grass genomes, have facilitated construction of an ordered gene map of chromosome 4A, embracing ≥85% of its total gene content, and have enabled precise localization of the various translocation and inversion breakpoints on chromosome 4A that differentiate it from its progenitor chromosome in the A genome diploid donor. The gene map of chromosome 4A, together with the emerging sequences of homoeologous wheat chromosome groups 4, 5 and 7, represent unique resources that will allow us to obtain new insights into the evolutionary dynamics between homoeologous chromosomes and syntenic chromosomal regions.


Hernandez, P., M. Martis, G. Dorado, M. Pfeifer, S. Gálvez, S. Schaaf, N. Jouve, H. Šimková, M. Valárik, J. Doležel and K. F. X. Mayer (2012). "Next-generation sequencing and syntenic integration of flow-sorted arms of wheat chromosome 4A exposes the chromosome structure and gene content." The Plant Journal 69(3): 377-386.