Plant Sequence Capture Optimised for Illumina Sequencing

Plant Sequence Capture is used for targeted resequencing of whole exomes (all exons of a genome) of complex genomes <em>e.g.</em> barley and its relatives (Mascher et al., 2013). Sequencing and computing costs are significantly reduced since only the greatly enriched and gene-coding part of the barley genome is targeted, that corresponds to only 1-2% of the entire genome. Thus, applications such as genetic diversity studies and the isolation of single genes (“cloning-by-sequencing”) are greatly facilitated. Here, a protocol is provided describing the construction of shotgun DNA libraries from genomic barley DNA for sequencing on the Illumina HiSeq/MiSeq systems. The shotgun DNA sequencing libraries are hybridized to an oligonucleotide pool (Exome Library) encompassing the whole exome of barley. The Exome Library is provided as a liquid array containing biotinylated probes (Roche/NimbleGen). Subsequently, genomic shotgun DNA fragments hybridized to the Exome Library are affinity-purified using streptavidin coated magnetic beads. The captured library is PCR-amplified and sequenced using high-throughput short read sequencing-by-synthesis.