Project description:While Illumina X technology has helped to reduce the cost of whole genome sequencing substantially, its application for bisulphite sequencing is not straightforward. We describe the optimization of a library preparation and sequencing approach that maximizes the yield and quality of sequencing, and how to eliminate a previously unrecognized artefact affecting several percent of bisulphite sequencing reads.
Project description:While Illumina X technology has helped to reduce the cost of whole genome sequencing substantially, its application for bisulphite sequencing is not straightforward. We describe the optimization of a library preparation and sequencing approach that maximizes the yield and quality of sequencing, and how to eliminate a previously unrecognized artefact affecting several percent of bisulphite sequencing reads.
Project description:While Illumina X technology has helped to reduce the cost of whole genome sequencing substantially, its application for bisulphite sequencing is not straightforward. We describe the optimization of a library preparation and sequencing approach that maximizes the yield and quality of sequencing, and how to eliminate a previously unrecognized artefact affecting several percent of bisulphite sequencing reads.
Project description:While Illumina X technology has helped to reduce the cost of whole genome sequencing substantially, its application for bisulphite sequencing is not straightforward. We describe the optimization of a library preparation and sequencing approach that maximizes the yield and quality of sequencing, and how to eliminate a previously unrecognized artefact affecting several percent of bisulphite sequencing reads.
Project description:Library preparation for whole genome bisulphite sequencing (WGBS) is challenging due to side effects of the bisulphite treatment, which leads to extensive DNA damage. Recently, a new generation of methods for bisulphite sequencing library preparation have been devised. They are based on initial bisulphite treatment of the DNA, followed by adaptor tagging of single stranded DNA fragments, and enable WGBS using low quantities of input DNA. In this study, we present a novel approach for quick and cost effective WGBS library preparation that is based on splinted adaptor tagging (SPLAT) of bisulphite-converted single-stranded DNA. Moreover, we validate SPLAT against three commercially available WGBS library preparation techniques, two of which are based on bisulphite treatment prior to adaptor tagging and one is a conventional WGBS method.
Project description:14 F1 individuals that resulted from crosses between a 420-CEN3 reporter line and met1-3/+ plants were subject to whole-genome bisulphite sequencing alongside Col wild-type and met1-3/+ controls
Project description:BACKGROUND:Comprehensive genome-wide DNA methylation profiling is critical to gain insights into epigenetic reprogramming during development and disease processes. Among the different genome-wide DNA methylation technologies, whole genome bisulphite sequencing (WGBS) is considered the gold standard for assaying genome-wide DNA methylation at single base resolution. However, the high sequencing cost to achieve the optimal depth of coverage limits its application in both basic and clinical research. To achieve 15×?coverage of the human methylome, using WGBS, requires approximately three lanes of 100-bp-paired-end Illumina HiSeq 2500 sequencing. It is important, therefore, for advances in sequencing technologies to be developed to enable cost-effective high-coverage sequencing. RESULTS:In this study, we provide an optimised WGBS methodology, from library preparation to sequencing and data processing, to enable 16-20× genome-wide coverage per single lane of HiSeq X Ten, HCS 3.3.76. To process and analyse the data, we developed a WGBS pipeline (METH10X) that is fast and can call SNPs. We performed WGBS on both high-quality intact DNA and degraded DNA from formalin-fixed paraffin-embedded tissue. First, we compared different library preparation methods on the HiSeq 2500 platform to identify the best method for sequencing on the HiSeq X Ten. Second, we optimised the PhiX and genome spike-ins to achieve higher quality and coverage of WGBS data on the HiSeq X Ten. Third, we performed integrated whole genome sequencing (WGS) and WGBS of the same DNA sample in a single lane of HiSeq X Ten to improve data output. Finally, we compared methylation data from the HiSeq 2500 and HiSeq X Ten and found high concordance (Pearson r?>?0.9×). CONCLUSIONS:Together we provide a systematic, efficient and complete approach to perform and analyse WGBS on the HiSeq X Ten. Our protocol allows for large-scale WGBS studies at reasonable processing time and cost on the HiSeq X Ten platform.
Project description:Bisulphite (BS) converted DNA from 2 paternal uniparental diploidies (pUPDs), one maternal (mUPD) and 5 control leukocytes samples were hybridized to the Infinium HumanMethylationEPIC BeadChip (Illumina), obtaining the BS DNA methylation profiles across approximately 850,000 CpGs. In addition, the 5 control leukocyte samples were also coverted using oxidative bisulphite (oxBS) treatment. The selective chemical oxidation of 5-hydroxymethylcytosine (5hmC) to 5-formylcytosine (5fC) and the deamination of the latter to uracil during the BS conversion allowed the quantification of independent 5-methylcytosine (5mC) and 5hmC methylation levels at every single CpG.