Single Molecule Real-Time (SMRT) Sequencing delivers reads that span the lengths of the majority of HLA class I and II genes. Unambiguously phase 4-field HLA types without imputation. With a more accurate and complete picture, gain deeper understanding of immune-related disease causality, graft-versus-host disease in hematopoietic transplantation, and drug hypersensitivity.
Scientists are utilizing long-read PacBio sequencing to provide uniquely comprehensive views of complex plant and animal genomes. These efforts are uncovering novel biological mechanisms, enabling progress in crop development, and much more. To date, scientists have published over 1000 papers with Single Molecule, Real-Time (SMRT) Sequencing, many covering breakthroughs in the plant and animal sciences. In this case study, we look at examples in model organisms Drosophila and C. elegans and non-model organisms coffee, Oropeitum, danshen, and sugarbeet, where SMRT Sequencing has contributed to a more accurate understanding of biology. These efforts underscore the broad applicability of long-read sequencing in…
The PacBio Platform includes an extensive software portfolio that employs key advantages of SMRT (Single Molecule, Real-Time) Sequencing technology: extraordinarily long reads, highest consensus accuracy, uniform coverage and simultaneous epigenetic characterization. Core elements of our analytical portfolio include SMRT Analysis software, DevNet and SMRT Compatible products.
With Single Molecule, Real-Time (SMRT) Sequencing and the Sequel System, you can easily and cost effectively generate highly accurate long reads (HiFi reads, >99% single-molecule accuracy) from genes or regions of interest ranging in size from several hundred base pairs to 20 kb. Target all types of variation across relevant genomic regions, including low complexity regions like repeat expansions, promoters, and flanking regions of transposable elements.
Although antiretroviral therapy (ART) is highly effective at suppressing HIV-1 replication, the virus persists as a latent reservoir in resting CD4+ T cells during therapy. This reservoir forms even when ART is initiated early after infection, but the dynamics of its formation are largely unknown. The viral reservoirs of individuals who initiate ART during chronic infection are generally larger and genetically more diverse than those of individuals who initiate therapy during acute infection, consistent with the hypothesis that the reservoir is formed continuously throughout untreated infection. To determine when viruses enter the latent reservoir, we compared sequences of replication-competent viruses…
The detection and identification of species of fungi in the environment using molecular methods heavily depends on reliable reference sequence databases. However, these databases are largely incomplete in terms of taxon coverage, and a significant effort is required from herbaria and living fungal collections for the mass-barcoding of well-identified and well-curated fungal specimens or strains. Here, a PacBio amplicon sequencing approach is applied to recent lichen herbarium specimens for the sequencing of the fungal ITS barcode, allowing a higher throughput sample processing than Sanger sequencing, which often required the use of cloning. Out of 96 multiplexed samples, a full-length ITS…
Human leukocyte antigen (HLA) is a gene complex known for its exceptional diversity across populations, importance in organ and blood stem cell transplantation, and associations of specific alleles with various diseases. We constructed a Japanese reference panel of class I HLA genes (ToMMo HLA panel), comprising a distinct set of HLA-A, HLA-B, HLA-C, and HLA-H alleles, by single-molecule, real-time (SMRT) sequencing of 208 individuals included in the 1070 whole-genome Japanese reference panel (1KJPN). For high-quality allele reconstruction, we developed a novel pipeline, Primer-Separation Assembly and Refinement Pipeline (PSARP), in which the SMRT sequencing and additional short-read data were used. The…
After initiating antiretroviral therapy (ART), a rapid decline in HIV viral load is followed by a long period of undetectable viremia. Viral outgrowth assay suggests the reservoir continues to decline slowly. Here, we use full-length sequencing to longitudinally study the proviral landscape of four subjects on ART to investigate the selective pressures influencing the dynamics of the treatment-resistant HIV reservoir. We find intact and defective proviruses that contain genetic elements favoring efficient protein expression decrease over time. Moreover, proviruses that lack these genetic elements, yet contain strong donor splice sequences, increase relatively to other defective proviruses, especially among clones. Our…
This tutorial provides an overview of the Long Amplicon Analysis (LAA) application. The LAA algorithm generates highly accurate, phased and full-length consensus sequences from long amplicons. Applications of LAA include HLA typing, alternative haplotyping, and localized de novo assemblies of targeted genes. This tutorial covers features of SMRT Link v5.0.0.
At AGBT 2017, Lars Paulin from the University of Helsinki presented this poster on whole genome sequencing of the virus responsible for progressive multifocal leukoencephalopathy, a rare and dangerous brain infection. His team used long amplicon analysis to resolve the whole virus genome from three patient samples, pooled them for SMRT Sequencing, and identified variants and rearrangements. This work represents the first time the viral genome was sequenced from patients.
PacBio SMRT Sequencing is fast changing the genomics space with its long reads and high consensus sequence accuracy, providing the most comprehensive view of the genome and transcriptome. In this webinar, I will talk about the various data analysis tools available in PacBio’s data analysis suite – SMRT Link – as well as 3rd party tools available. Key applications addressed in this talk are: Genome Assemblies, Structural Variant Analysis, Long Amplicon and Targeted Sequencing, Barcoding Strategies, Iso-Seq Analysis for Full-length Transcript Sequencing
The correct phasing of genetic variations is a key challenge for many applications of DNA sequencing. Allele-level resolution is strongly preferred for histocompatibility sequencing where recombined genes can exhibit different compatibilities than their parents. In other contexts, gene complementation can provide protection if deleterious mutations are found on only one allele of a gene. These problems are especially pronounced in immunological domains given the high levels of genetic diversity and recombination seen in regions like the Major Histocompatibility Complex. A new tool for analyzing Single Molecule, Real-Time (SMRT) Sequencing data – Long Amplicon Analysis (LAA) – can generate highly accurate,…
While the identification of individual SNPs has been readily available for some time, the ability to accurately phase SNPs and structural variation across a haplotype has been a challenge. With individual reads of an average length of 9 kb (P5-C3), and individual reads beyond 30 kb in length, SMRT Sequencing technology allows the identification of mutation combinations such as microdeletions, insertions, and substitutions without any predetermined reference sequence. Long- amplicon analysis is a novel protocol that identifies and reports the abundance of differing clusters of sequencing reads within a single library. Graphs generated via hierarchical clustering of individual sequencing reads…
Mitochondrial DNA (mtDNA) is a compact, double-stranded circular genome of 16,569 bp with a cytosine-rich light (L) chain and a guanine-rich heavy (H) chain. mtDNA mutations have been increasingly recognized as important contributors to an array of human diseases such as Parkinson’s disease, Alzheimer’s disease, colorectal cancer and Kearns–Sayre syndrome. mtDNA mutations can affect all of the 1000-10,000 copies of the mitochondrial genome present in a cell (homoplasmic mutation) or only a subset of copies (heteroplasmic mutation). The ratio of normal to mutant mtDNAs within cells is a significant factor in whether mutations will result in disease, as well as…