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.
With the Sequel II System powered by Single Molecule, Real-Time (SMRT) Sequencing technology and SMRT Link v8.0, 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.
Explore the types of human genomic variation and the diseases known to be caused by structural variants.
Structural variation accounts for much of the variation among human genomes. Structural variants of all types are known to cause Mendelian disease and contribute to complex disease. Learn how long-read sequencing is enabling detection of the full spectrum of structural variants to advance the study of human disease, evolution and genetic diversity.
Explore how long-read sequencing enables solving of rare and mendelian diseases.
During the past decade, the search for pathogenic mutations in rare human genetic diseases has involved huge efforts to sequence coding regions, or the entire genome, using massively parallel short-read sequencers. However, the approximate current diagnostic rate is
The widespread occurrence of repetitive stretches of DNA in genomes of organisms across the tree of life imposes fundamental challenges for sequencing, genome assembly, and automated annotation of genes and proteins. This multi-level problem can lead to errors in genome and protein databases that are often not recognized or acknowledged. As a consequence, end users working with sequences with repetitive regions are faced with ‘ready-to-use’ deposited data whose trustworthiness is difficult to determine, let alone to quantify. Here, we provide a review of the problems associated with tandem repeat sequences that originate from different stages during the sequencing-assembly-annotation-deposition workflow, and…
Tandem repeat (TR) expansions have been implicated in dozens of genetic diseases, including Huntington’s Disease, Fragile X Syndrome, and hereditary ataxias. Furthermore, TRs have recently been implicated in a range of complex traits, including gene expression and cancer risk. While the human genome harbors hundreds of thousands of TRs, analysis of TR expansions has been mainly limited to known pathogenic loci. A major challenge is that expanded repeats are beyond the read length of most next-generation sequencing (NGS) datasets and are not profiled by existing genome-wide tools. We present GangSTR, a novel algorithm for genome-wide genotyping of both short and…
Tandemly repeated DNA is highly mutable and causes at least 31 diseases, but it is hard to detect pathogenic repeat expansions genome-wide. Here, we report robust detection of human repeat expansions from careful alignments of long but error-prone (PacBio and nanopore) reads to a reference genome. Our method is robust to systematic sequencing errors, inexact repeats with fuzzy boundaries, and low sequencing coverage. By comparing to healthy controls, we prioritize pathogenic expansions within the top 10 out of 700,000 tandem repeats in whole genome sequencing data. This may help to elucidate the many genetic diseases whose causes remain unknown.
In this ASHG workshop presentation, Janet Song of Stanford School of Medicine shared research on resolving a tandem repeat array implicated in bipolar disorder and schizophrenia. These psychiatric diseases share a number of genomic risk variants, she noted, but scientists continue to search for a specific causal variant in the CACNA1C gene suggested by previous genome-wide association studies. SMRT Sequencing of this region in 16 individuals identified a series of 30-mer repeats, containing a total of about 50 variants. Analysis showed that 10 variants were linked to protective or risk haplotypes. Song aims to study the function of these variants…
In this PacBio User Group Meeting presentation, Jonas Korlach and Roberto Lleras share the latest updates to the structural variation application and analysis tools.
In this presentation Fritz Sedlazeck describes his latest work to obtain comprehensive genomes leveraging long-read sequencing and linked reads.
Robert Sebra reports the use of SMRT Sequencing at the Icahn Institute and presents some early data from the new Sequel System. Topics include: Targeted sequencing applications for CYP2D6 metabolism and Gaucher disease, tandem repeat detection in FTD/ALS patients, structural variation detection for Goldenhar Syndrome, inverted PCR assays for detection of DNA damage in Glioblastome, whole gene BRCA sequencing, and sensitive somatic variant detection in heterogeneous tissues.
Simon Chan, UC Davis on how PacBio long read sequencing revealed higher order repeats in centromeres of switchgrass which would have been hidden if you are restricted by the much shorter Sanger reads.
Explore human genetic variation and learn how SMRT Sequencing uncovers the full spectrum of structural variation to advance understanding of genetic disease and broaden our knowledge of human diversity.