To bring personalized medicine to all patients, cancer researchers need more reliable and comprehensive views of somatic variants of all sizes that drive cancer biology.
The UK’s National Collection of Type Cultures (NCTC) is a unique collection of more than 5,000 expertly preserved and authenticated bacterial cultures, many of historical significance. Founded in 1920, NCTC is the longest established collection of its type anywhere in the world, with a history of its own that has reflected — and contributed to — the evolution of microbiology for more than 100 years.
Mike Snyder from Stanford University has published recent papers in Nature Biotechnology and PNAS using SMRT Sequencing for transcriptome analysis and demonstrated that long reads enable full coverage of RNA molecules. He discusses that work and his views on long-read sequencing and transcriptomics in this podcast.
The Mike Schatz lab at Cold Spring Harbor is well know for de novo genome assemblies and their work on structural variation in cancer genomes. In this Mendelspod podcast, lab leader, Mike Schatz, and doctorate student, Maria Nattestad tell of two new projects that include the de novo assembly of a very difficult but important flatworm genome and, secondly, making better variant calls for oncogenes such as HER2.
Steve Kujawa from PacBio presents an AGBT poster reporting a study that characterized the use of SMRT Sequencing for the detection of low-frequency somatic variants. A multiplexed reference standard was amplified using the Multiplicom assay and sequenced on both the PacBio RS II and MiSeq System. Results indicate good concordance between the sequencing platforms, even at very low mutation frequencies.
PacBio Sequencing is characterized by very long sequence reads (averaging > 10,000 bases), lack of GC-bias, and high consensus accuracy. These features have allowed the method to provide a new gold standard in de novo genome assemblies, producing highly contiguous (contig N50 > 1 Mb) and accurate (> QV 50) genome assemblies. We will briefly describe the technology and then highlight the full workflow, from sample preparation through sequencing to data analysis, on examples of insect genome assemblies, and illustrate the difference these high-quality genomes represent with regard to biological insights, compared to fragmented draft assemblies generated by short-read sequencing.
PacBio bioinformatician Aaron Wenger presents this ASHG 2016 poster demonstrating human structural variation detection at varying coverage levels with SMRT Sequencing on the Sequel System. Results were compared to truth sets for well-characterized genomes. Results indicate that even low coverage of SMRT Sequencing makes it possible to detect hundreds of SVs that are missed in high-coverage short-read sequencing data.
PacBio’s Jenny Ekholm presents this ASHG 2016 poster on a new method being developed that enriches for unamplified DNA and uses SMRT Sequencing to characterize repeat expansion disorders. Incorporating the CRISPR/Cas9 system to target specific genes allows for amplification-free enrichment to preserve epigenetic information and avoid PCR bias. Internal studies have shown that the approach can successfully be used to target and sequence the CAG repeat responsible for Huntington’s disease, the repeat associated with ALS, and more. The approach allows for pooling many samples and sequencing with a single SMRT Cell.
From Mendelspod: Jonas Korlach is a natural storyteller—a rare trait in a scientist who is more comfortable presenting data than talking of himself. Jonas is the co-inventor of PacBio’s SMRT (single molecule, real time) sequencing, and we wanted to hear from him directly how it all got started, and also when the team realized that they had something big with long reads and close to 100X coverage. How many of us can boast of hitting it out of the park on our first try?
Valerie Schneider of the National Center for Biotechnology Information discuss how the Genome Reference Consortium (GRC) is bringing more ethnic diversity to the latest human reference assembly (GRCh38) by adding patches and alternate loci scaffolds. Scientists working with population graphs are among the early adopters of these new alternate loci scaffolds. She also discusses work underway at the McDonnell Genome Institute at Washington University to generate a set of high-quality, de novo whole genomes from a wide variety of populations. The new ethnic genomes “are also intended to stand on their own as complements to the reference so users can…
Melissa Laird Smith discussed how the Icahn School of Medicine at Mount Sinai uses long-read sequencing for translational research. She gave several examples of targeted sequencing projects run on the Sequel System including CYP2D6, phased mutations of GLA in Fabry’s disease, structural variation breakpoint validation in glioblastoma, and full-length immune profiling of TCR sequences.
Jonas Korlach spoke about recent SMRT Sequencing updates, such as latest Sequel System chemistry release (1.2.1) and updates to the Integrative Genomics Viewer that’s now update optimized for PacBio data. He presented the recent data release of structural variation detected in the NA12878 genome, including many more insertions and deletions than short-read-based technologies were able to find.
In this podcast, Gibbs shares his perspective on the complementary roles genomics and genetics plays in driving our understanding of human biology. Richard says that the Human genome project was actually a departure from had been typical in the field of human genetics. He notes, “there really was this departure between human genetics and genomics for a decade and a half or more, really because of the demands of doing the genome project there was too much to do to stop and think about some of these more fundamental problems in genetics.” Gibbs observes that we have now entered a…
Early detection of colorectal cancer (CRC) and its precursor lesions (adenomas) is crucial to reduce mortality rates. The fecal immunochemical test (FIT) is a non-invasive CRC screening test that detects the blood-derived protein hemoglobin. However, FIT sensitivity is suboptimal especially in detection of CRC precursor lesions. As adenoma-to-carcinoma progression is accompanied by alternative splicing, tumor-specific proteins derived from alternatively spliced RNA transcripts might serve as candidate biomarkers for CRC detection.