The PacBio sequencing is a powerful approach to study the DNA or RNA sequences in a longer scope. It is especially useful in exploring the complex structural variants generated by random integration or multiple rearrangements of internal or external sequences. However, there is still no tool designed to uncover their structural organization in the host genome. Here, we present a tool, TSD, for complex structural variant discovery using PacBio targeted sequencing data. It allows researchers to identify and visualize the genomic structures of targeted sequences by unlimited splitting, alignment and assembly of long PacBio reads. Application to the sequencing data…
The sequence and assembly of human genomes using long-read sequencing technologies has revolutionized our understanding of structural variation and genome organization. We compared the accuracy, continuity, and gene annotation of genome assemblies generated from either high-fidelity (HiFi) or continuous long-read (CLR) datasets from the same complete hydatidiform mole human genome, CHM13. We find that the HiFi sequence data assemble an additional 10% of duplicated regions and more accurately represent the structure of large tandem repeats, as validated with orthogonal analyses. Additionally, the HiFi genome assembly was generated in significantly less time with fewer computational resources than the CLR assembly. Although…
The wide implementation of next-generation sequencing (NGS) technologies has revolutionized the field of medical genetics. However, the short read lengths of currently used sequencing approaches pose a limitation for identification of structural variants, sequencing repetitive regions, phasing alleles and distinguishing highly homologous genomic regions. These limitations may significantly contribute to the diagnostic gap in patients with genetic disorders who have undergone standard NGS, like whole exome or even genome sequencing. Now, the emerging long-read sequencing (LRS) technologies may offer improvements in the characterization of genetic variation and regions that are difficult to assess with the currently prevailing NGS approaches. LRS…
Read our product brochure to learn more about how SMRT Sequencing and the Sequel II System and will accelerate your research by delivering highly accurate long reads to provide the most comprehensive view of genomes, transcriptomes and epigenomes.
Single Molecule, Real-Time (SMRT) Sequencing on the Sequel II System enables easy and affordable generation of high-quality de novo assemblies of even the most complex genomes. With megabase-size contig N50s, consensus accuracies >99.99%, and tools for phasing haplotypes you can capture undetected SNVs, fully intact genes, and regulatory regions embedded in complex structures that fragmented draft genomes often miss.
The Sequel II System, powered by Single Molecule, Real Time (SMRT) Technology, delivers highly accurate long reads for a comprehensive view of genomes, transcriptomes and epigenomes.
With the Sequel II System powered by Single Molecule, Real-Time (SMRT) Sequencing technology and SMRT Link v7.0, you can affordably and effectively detect structural variants (SVs), copy number variants, and large indels ranging in size from tens to thousands of base pairs. PacBio long-read whole genome sequencing comprehensively resolves variants in an individual with high precision and recall. For population genetics and pedigree studies, joint calling powers rapid discovery of common variants within a sample cohort.
With highly accurate long reads (HiFi reads) from the Sequel II System, powered by Single Molecule, Real-Time (SMRT) Sequencing technology, you can comprehensively detect variants in a human genome. HiFi reads provide high precision and recall for single nucleotide variants (SNVs), indels, structural variants (SVs), and copy number variants (CNVs), including in difficult-to-map repetitive regions.
Current programmable nuclease-based methods (for example, CRISPR-Cas9) for the precise correction of a disease-causing genetic mutation harness the homology-directed repair pathway. However, this repair process requires the co-delivery of an exogenous DNA donor to recode the sequence and can be inefficient in many cell types. Here we show that disease-causing frameshift mutations that result from microduplications can be efficiently reverted to the wild-type sequence simply by generating a DNA double-stranded break near the centre of the duplication. We demonstrate this in patient-derived cell lines for two diseases: limb-girdle muscular dystrophy type 2G (LGMD2G)1 and Hermansky-Pudlak syndrome type 1 (HPS1)2. Clonal…
A complete and accurate genome sequence provides a fundamental tool for functional genomics and DNA-informed breeding. Here, we assemble a high-quality genome (contig N50 of 6.99?Mb) of the apple anther-derived homozygous line HFTH1, including 22 telomere sequences, using a combination of PacBio single-molecule real-time (SMRT) sequencing, chromosome conformation capture (Hi-C) sequencing, and optical mapping. In comparison to the Golden Delicious reference genome, we identify 18,047 deletions, 12,101 insertions and 14 large inversions. We reveal that these extensive genomic variations are largely attributable to activity of transposable elements. Interestingly, we find that a long terminal repeat (LTR) retrotransposon insertion upstream of…
Accurate and fast aligners are required to handle the steadily increasing volume of sequencing data. Here we present an approach allowing performant alignments of short reads (Illumina) as well as long reads (Pacific Bioscience, Ultralong Oxford Nanopore), while achieving high accuracy, based on a universal three-stage scheme. It is also suitable for the discovery of insertions and deletions that originate from structural variants. We comprehensively compare our approach to other state-of-the-art aligners in order to confirm its performance with respect to accuracy and runtime. As part of our algorithmic scheme, we introduce two line sweep-based techniques called "strip of consideration"…
Past large scale cancer genome sequencing efforts, including The Cancer Genome Atlas and the International Cancer Genome Consortium, have utilized short-read sequencing, which is well-suited for detecting single nucleotide variants (SNVs) but far less reliable for detecting variants larger than 20 base pairs, including insertions, deletions, duplications, inversions and translocations. Recent same-sample comparisons of short- and long-read human reference genome data have revealed that short-read resequencing typically uncovers only ~4,000 structural variants (SVs, =50 bp) per genome and is biased towards deletions, whereas sequencing with PacBio long-reads consistently finds ~20,000 SVs, evenly balanced between insertions and deletions. This discovery has…
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.