In this ASHG 2020 PacBio Workshop Jonas Korlach, CSO, shares how the new PacBio Sequel IIe System makes highly accurate long-read sequencing easy and affordable so?all scientists can gain comprehensive views of human genomes and transcriptomes. He goes on to provide updates on the applications including human WGS for variant detection, de novo genome assembly, single-cell full-length RNA sequencing, and targeted sequencing using PCR and No-Amp methods.
In this ASHG 2020 CoLab presentation hear Principal Scientists, Aaron Wenger and Elizabeth Tseng share how highly accurate long reads (HiFi reads) provide comprehensive variant detection for both genomes and transcriptomes. Aaron Wenger describes how new improvements in protocols and analysis methods have increased scalability and accuracy of variant calling. As demonstrated in the precisionFDA Truth Challenge V2, HiFi reads (>99% accurate, 15 kb – 20 kb) now outperform short reads for single nucleotide and structural variant calling and match for small indels. This includes calling >30,000 small variants and >10,000 structural variants missed by short reads, many in medically…
PacBio CSO Jonas Korlach describes the Iso-Seq method for full-length transcript isoform characterization using SMRT Sequencing. He presents published research using the method for full isoform characterization, including papers from Stanford scientists who analyzed full transcriptomes with SMRT Sequencing. With the Iso-Seq method, researchers found novel isoforms and novel genes even in well-studied cell lines.
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.
Chongyuan Luo from the Salk Institute for Biological Studies describes sequencing three strains of Arabidopsis thaliana using PacBio technology. The goal: uncover structural variants that have been missed by short-read and other sequencers. Luo notes that PacBio sequencing provides highly accurate SNP detection and also extends the mappability of reads beyond what is possible with short-read data, producing better and more accurate assemblies.
At the PacBio ASHG workshop, Hagen Tilgner describes how he used long-read sequencing with Iso-Seq method to generate the first personal transcriptomes for three individuals. From these three family members, he and his collaborators were able to unambigously assign allele-specific RNA haplotypes, including HLA haplotypes, and demonstrated Mendelian inheritance of RNA molecules.
Jonas Korlach, Chief Scientific Officer at PacBio, discussed the technology waves that have followed the initial human genome sequencing project, where we are today, and where we are going. Today, we are in what Korlach calls the 4th wave, where more comprehensive whole-genome re-sequencing is occurring, and we are nearing the 5th, when we will actually be able to free ourselves from reference genomes and sequence everything de novo.
David Kudrna, Rod Wing, and the Arizona Genomics Institute (AGI) plan to fully sequence and annotate the genomes and transcriptomes of 3-4 accessions from each of the estimated 9-15 subpopulation of rice. These subpopulation-specific references will be used to map resequencing data of 3,000 individuals for variation discovery, GWAS, and genomic selection studies to address important traits such as biotic and abiotic stress tolerances, yield, and grain quality. Here Dr. Kudrna presents the first high-quality genome sequence of the rice variety Nagina22. AGI produced and assembled 65-fold coverage of SMRT Sequencing data, resulting in an assembly of 373 Mb with…
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 AGBT 2017 talk, PacBio CSO Jonas Korlach provided a technology roadmap for the Sequel System, including plans the continue performance and throughput increases through early 2019. Per SMRT Cell throughput of the Sequel System is expected to double this year and again next year. Together with a new higher-capacity SMRT Cell expected to be released by the end of 2018, these improvements result in a ~30-fold increase or ~150 Gb / SMRT Cell allowing a real $1000 real de novo human genome assembly. Also discussed: Additional application protocol improvements, new chemistry and software updates, and a look at…
In this AGBT 2017 poster, the University of Helsinki’s Petri Auevinen reports on efforts to understand bacteria that grow on, and subsequently spoil, food. This analysis monitored DNA modifications and transcriptomic changes in three species of lactic acid bacteria. Scientists discovered that the organisms’ metabolic profiles change substantially when grown together compared to those cultured individually, and are now studying how Cas protein activity changes under these conditions too.
Tremendous flexibility is maintained in the human proteome via alternative splicing, and cancer genomes often subvert this flexibility to promote survival. Identification and annotation of cancer-specific mRNA isoforms is critical to understanding how mutations in the genome affect the biology of cancer cells. While microarrays and other NGS-based methods have become useful for studying transcriptomes, these technologies yield short, fragmented transcripts that remain a challenge for accurate, complete reconstruction of splice variants. The Iso-Seq method developed at PacBio offers the only solution for direct sequencing of full-length, single-molecule cDNA sequences needed to discover biomarkers for early detection and cancer stratification,…
In this PAG 2018 presentation, Tanya Renner of Pennsylvania State University shares research using PacBio SMRT Sequencing to understand the genomes and transcriptomes of carnivorous plants. She describes the humped bladderwort, Utricularia gibba, as having an extreme genome due to its small size (100 Mbp) despite containing numerous tandem gene duplications and having undergone two whole genome duplications. Renner shares ongoing research into two Drosera species, commonly known as sundews, which through whole genome sequencing are illuminating carnivorous plant genome structural evolution including the transition from monocentric to holocentric chromosomes.
In this presentation Fritz Sedlazeck describes his latest work to obtain comprehensive genomes leveraging long-read sequencing and linked reads.
In this PAG 2018 presentation, John Williams of University of Adelaide, presents research on using PacBio SMRT Sequencing to explore the genetic origins of cattle subspecies, Angus (Bos taurus taurus) and Brahman (Bos taurus indicus). He shares RNA sequencing data using the PacBio Iso-Seq method to compare transcriptomes and phase allelic expression and describes how the IsoPhase technique enables evaluation of SNPs through transcriptome mapping back to the single genome of a cross-bred individual. Using a genomic and transcriptomic approach, two high-quality genomes from a single individual and gene isoforms specific to each subspecies are being identified.