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.
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.
The 17th International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated "consensus" HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate…
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…
Benchmark small variant calls are required for developing, optimizing and assessing the performance of sequencing and bioinformatics methods. Here, as part of the Genome in a Bottle (GIAB) Consortium, we apply a reproducible, cloud-based pipeline to integrate multiple short- and linked-read sequencing datasets and provide benchmark calls for human genomes. We generate benchmark calls for one previously analyzed GIAB sample, as well as six genomes from the Personal Genome Project. These new genomes have broad, open consent, making this a 'first of its kind' resource that is available to the community for multiple downstream applications. We produce 17% more benchmark…
HLA*LA implements a new graph alignment model for HLA type inference, based on the projection of linear alignments onto a variation graph. It enables accurate HLA type inference from whole-genome (99% accuracy) and whole-exome (93% accuracy) Illumina data; from long-read Oxford Nanopore and Pacific Biosciences data (98% accuracy for whole-genome and targeted data); and from genome assemblies. Computational requirements for a typical sample vary between 0.7 and 14 CPU hours per sample.HLA*LA is implemented in C?++ and Perl and freely available as a bioconda package or from https://github.com/DiltheyLab/HLA-LA (GPL v3).Supplementary data are available online.© The Author(s) 2019. Published by Oxford…
HLA matching at an allelic-level resolution for volunteer unrelated donor (VUD) hematopoietic cell transplanta- tion (HCT) results in improved survival and fewer post-transplant complications. Limitations in typing technolo- gies used for the hyperpolymorphic HLA genes have meant that variations outside of the antigen recognition domain (ARD) have not been previously characterized in HCT. Our aim was to explore the extent of diversity out- side of the ARD and determine the impact of this diversity on transplant outcome. Eight hundred ninety-one VUD-HCT donors and their recipients transplanted for a hematologic malignancy in the United Kingdom were ret- rospectively HLA typed at…
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.
In this AGBT presentation, Marty Badgett shares a look at the latest results from circular consensus sequencing (CCS) mode for highly accurate reads and data from our soon-to-be-released Sequel II System. As he demonstrates, CCS reads cover the same molecule many times, delivering high consensus accuracy despite noisy raw reads; on average, reaching 10 passes achieves Q30 accuracy. Badgett offers several examples where this is useful, such as pharmacogenomic gene analysis and resolving metagenomic communities. He also provides an update on the Iso-Seq method, which can now segregate transcripts into haplotype-specific alleles using a new tool called Iso-Phase.