The highly polymorphic CYP2D6 gene impacts the metabolism of 25% of the mostly prescribed drugs. Thus, accurate identification of variant CYP2D6 alleles in individuals is necessary for personalized medicine. PacBio HiFi sequencing produces long and accurate reads to identify variant regions. Here, we describe an end-to-end workflow for the characterization of full-length CYP2D6 by HiFi sequencing.
There are many clinically important genes in “dark” regions of the human genome. These regions are characterized as dark due to a paucity of NGS coverage as a result of short-read sequencing or mapping difficulties. Low NGS sequencing yield can arise in these regions due to the presence of various repeat elements or biased base composition while inaccurate mapping can result from segmental duplications. Long-read sequencing coupled with an optimized, robust enrichment method has the potential to illuminate these dark regions.
Many genetic diseases are mapped to structurally complex loci. These regions contain highly similar paralogous alleles (>99% identity) that span kilobases within the human genome. Comprehensive screening for pathogenic variants is incomplete and labor intensive using short-reads or optical mapping. In contrast, long-range amplification and PacBio HiFi sequencing fully and directly resolve and phase a wide range of pathogenic variants without inference. To capitalize on the accuracy of HiFi data we designed a new amplicon analysis tool, pbAA. pbAA can rapidly deconvolve a mixture of haplotypes, enabling precise diplotyping, and disease allele classification.
Learn how Single Molecule, Real-Time (SMRT) Sequencing and the Sequel IIe System and will accelerate your research by delivering highly accurate long reads to provide the most comprehensive view of genomes, transcriptomes and epigenomes.
Learn why it is critically important to understand accuracy in DNA sequencing to distinguish important biological information from sequencing errors.
Discover the benefits of HiFi reads and learn how highly accurate long-read sequencing provides a single technology solution across a range of applications.
With PacBio Single Molecule, Real-Time (SMRT) Sequencing on the Sequel IIe System you can characterize whole genomes and transcriptomes with just one SMRT Cell. Explore our applications and pricing to get your sequencing project started.
With the PacBio no-amplification (No-Amp) targeted sequencing method, you can now sequence through previously inaccessible regions of the genome to provide base-level resolution of disease-causing repeat expansions. By combining the CRISPR-Cas9 enrichment method with Single Molecule, Real-Time (SMRT) Sequencing on the Sequel Systems you are no longer limited by hard-to-amplify targets.
In this presentation, Dr. Marka van Blitterswijk shares the exciting results of her most recent targeted long-read sequencing study. Together with her colleagues, she performed No-Amp sequencing to examine an expanded GGGGCC-repeat in C9orf72, which causes fatal neurodegenerative diseases. Her team assessed the length of the C9orf72 expansion, as well as the presence of interruptions, thus revealing relevant clinico-pathological associations and demonstrating how powerful No-Amp sequencing is.
In this talk, Dr. Meredith Course presents her research on uncovering a 69-bp human-specific tandem repeat expansion in the final intron of WDR7. Larger repeat copy number is significantly associated with sporadic ALS cases, suggesting that it plays a role in disease susceptibility. Long-read sequencing reveals remarkable internal nucleotide variation, which was harnessed to determine the evolutionary origin of the expansion, its mechanism of replication, and its current state in modern-day humans. Each copy of the repeat has been determined to be able to form microRNAs and aggregate in cells and may sequester ALS-related RNA-binding proteins.
In this talk, Dr. Stephanie Tome describes using PacBio Single Molecule, Real-Time (SMRT) Sequencing to precisely measure large CTG repeat size and identify sequence interruptions of expanded allele to understand clinical and genetic variability in DM1 patients, sequencing several DM1 patients with CTG repeat expansion ranging from 130 to > 1000 CTG repeats on the Sequel I and II Systems from amplicons. She obtained more than 77% full DM1 reads per sample, with >70% of the reads from expanded alleles. The data includes long reads in the expected size range for all samples, including DM1 patients with more than 1000…
In this talk, Dr. Zachary McEachin describes how No-Amp targeted sequencing enables sequencing analysis of multiple (at least 15) Ataxia-related repeat expansion loci in one assay, presenting example sequencing results with selected samples from Ataxia patients and patients with unknown diagnostics. He demonstrates how PacBio HiFi sequencing with the No-Amp approach could provide repeat expansion and sequence interruption information at the target loci that is not available with PCR or southern-blot based diagnostics assays.