Spinocerebellar ataxia type 10 (SCA10) is a rare autosomal-dominant disorder caused by an expanded intronic pentanucleotide repeat in the ATXN10 gene. This repeat expansion when fully penetrant can be typically expected between 850 and 4500 repeats or 4.25 to 22.5 kb. Current diagnostic assays using PCR-based methods or Southern blotting cannot accurately size or resolve the genomic structure of the ATXN10 repeat. In this talk, Dr. Birgitt Schuele elaborates that CRISPR-Cas9 enrichment/single molecule real time (SMRT) sequencing technology and optical mapping now allow for accurate sizing of the repeat expansion, repeat composition, and can resolve somatic mosaicism, which are critical…
In this talk, Dr. Flora Tassone focuses on the identification of alternative splicing isoforms at the FMR1 locus (both sense and antisense direction) in individual carriers of the FMR1 premutation allele, using the SMRT Sequencing approach. The characterization of a transcriptional profile could help to define a biomarker for monitoring disease progression and development.
Many neurological diseases result from expansion of unstable variable nucleotide tandem repeats (VNTRs) that influence gene transcription of neighboring genes. In this talk, Dr. Henne Holstege presents research that investigated VNTRs across several genomes including a 115-year-old cognitively healthy individual. She and her group found that the genes that contained most VNTRs, of which PTPRN2 and DLGAP2 are the most prominent examples, were found to be predominantly expressed in the brain and associated with a wide variety of neurological disorders.
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.
AGBT 2013 Presentation Slides: Cold Spring Harbor Laboratory's Michael Schatz presented strategies for de novo assembly of crop genomes with PacBio technolgy.
PacBio 2013 User Group Meeting Presentation Slides: Lance Hepler from UC San Diego’s Center for AIDS Research used the PacBio RS to study intra-host diversity in HIV-1. He compared PacBio’s performance to that of 454® sequencer, the platform he and his team previously used. Hepler noted that in general, there was strong agreement between the platforms; where results differed, he said that PacBio data had significantly better reproducibility and accuracy. “PacBio does not suffer from local coverage loss post-processing, whereas 454 has homopolymer problems,” he noted. Hepler said they are moving away from using 454 in favor of the PacBio…
PacBio 2013 User Group Meeting Presentation Slides: Lisbeth Guethlein from Stanford University School of Medicine looked at highly repetitive and variable immune regions of the orangutan genome. Guethlein reported that “PacBio managed to accomplish in a week what I have been working on for a couple years” (with Sanger sequencing), and the results were concordant. “Long story short, I was a happy customer.”
SFAF 2014 Presentation Slides: James Gurtowski of Cold Spring Harbor Laboratory (CSHL) shared assembly results for a variety of eukaryotic genomes, including yeast, arabidopsis, and rice.
PacBio 2014 User Group Meeting Presentation Slides: Anne Deslattes Mays of Georgetown University discussed how PacBio provided the necessary full-length isoform information to allow characterization of isoform distribution by sub-cell population.
PacBio 2014 User Group Meeting Presentation Slides: Alisha Holloway of the Gladstone Institutes presented on the use of isoform sequencing (Iso-Seq) to improve the annotation of the chicken genome as a model reference for cardiovascular research.
Generating de novo reference genome assemblies for non-model organisms is a laborious task that often requires a large amount of data from several sequencing platforms and cytogenetic surveys. By using PacBio sequence data and new library creation techniques, we present a de novo, high quality reference assembly for the goat (Capra hircus) that demonstrates a primarily sequencing-based approach to efficiently create new reference assemblies for Eukaryotic species. This goat reference genome was created using 38 million PacBio P5-C3 reads generated from a San Clemente goat using the Celera Assembler PBcR pipeline with PacBio read self-correction. In order to generate the…
The goat (Capra hircus) remains an important livestock species due to the species’ ability to forage and provide milk, meat and wool in arid environments. The current goat reference assembly and annotation borrows heavily from other loosely related livestock species, such as cattle, and may not reflect the unique structural and functional characteristics of the species. We present preliminary data from a new de novo reference assembly for goat that primarily utilizes 38 million PacBio P5-C3 reads generated from an inbred San Clemente goat. This assembly consists of only 5,902 contigs with a contig N50 size of 2.56 megabases which…