At DuPont Pioneer, DNA sequencing is paramount for R&D to reveal the genetic basis for traits of interest in commercial crops such as maize, soybean, sorghum, sunflower, alfalfa, canola, wheat, rice, and others. They cannot afford to wait the years it has historically taken for high-quality reference genomes to be produced. Nor can they rely on a single reference to represent the genetic diversity in its germplasm.
At AGBT 2017, Margaret Roy from Calico Life Sciences discussed a de novo genome sequencing effort for the naked mole rat. This animal has a remarkably long life span and resistance to cancer, both of which make it interesting for studies of life extension. The team is using SMRT Sequencing for a more complete, contiguous assembly than the two existing short-read-based assemblies. Included: data from the Sequel System.
In this PacBio User Group Meeting presentation, Tim Smith of the USDA’s Agricultural Research Service describes efforts to generate reference-grade genome assemblies for various bovine species and analyze them to understand factors such as how selective breeding has affected certain breeds. Genome assemblies he presents span cattle, water buffalo, and gaur. Smith shows data for each assembly, noting that as data production shifted to the Sequel System, long-read PacBio data became even better at producing highly contiguous assemblies.
In this webinar, Barbara Block of Stanford University and Paul Peluso of PacBio describe how plant and animal whole genome sequencing remains a challenging endeavor, particularly due to genome size, high density of repetitive elements, and heterozygosity. Because of this, often only a single, fragmented reference genome is available for a species, genus, or even family, limiting the ability to answer important biological questions. Looking at the trends in genome assembly and annotation over the past year, such as pan-genomes and phasing, this webinar explores how Single Molecule, Real-Time (SMRT) Sequencing is utilized to develop long-lasting genomic resources, supporting research…
In this presentation at PAG 2020, Bart Nijland of Genetwister Technologies explains how his team set out to make a haplotype-aware assembly of the highly complex tetraploid Rosa x hybrida L. genome in order to capture its full range of genetic variation. HiFi reads generated from PacBio’s Sequel II System have made it possible to parse out critical information from many of the plant’s parental genes.
Hear how scientists have used PacBio sequencing to develop pangenome collections and to study population genetics of plant and animal species to power their research. Learn about the advantages of sequencing multiple individuals to gain comprehensive views of genetic variation, and understand the speed, cost, and accuracy benefits of using highly accurate long reads (HiFi reads) to sequence your species of interest.
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…
As the costs for genome sequencing have decreased the number of “genome” sequences have increased at a rapid pace. Unfortunately, the quality and completeness of these so–called “genome” sequences have suffered enormously. We prefer to call such genome assemblies as “gene assembly space” (GAS). We believe it is important to distinguish GAS assemblies from reference genome assemblies (RGAs) as all subsequent research that depends on accurate genome assemblies can be highly compromised if the only assembly available is a GAS assembly.
Goat is an important source of milk, meat, and fiber, especially in developing countries. An advantage of goats as livestock is the low maintenance requirements and high adaptability compared to other milk producers. The global population of domestic goats exceeds 800 million. In Africa, goat production is characterized by low productivity levels, and attempts to introduce more productive breeds have met with poor success due in part to nutritional constraints. It has been suggested that incorporation of selective breeding within the herds adapted for survival could represent one approach to improving food security across Africa. A recently produced genome assembly…
Drought is responsible for much of the global losses in crop yields and understanding how plants naturally cope with drought stress is essential for breeding and engineering crops for the changing climate. Resurrection plants desiccate to complete dryness during times of drought, then “come back to life” once water is available making them an excellent model for studying drought tolerance. Understanding the molecular networks governing how resurrection plants handle desiccation will provide targets for crop engineering. Oropetium thomaeum (Oro) is a resurrection plant that also has the smallest known grass genome at 250 Mb compared to Brachypodium distachyon (300 Mb)…
Arabica coffee, revered for its taste and aroma, has a complex genome. It is an allotetraploid (2n=4x=44) with a genome size of approximately 1.3 Gb, derived from the recent (< 0.6 Mya) hybridization of two diploid progenitors (2n=2x=22), C. canephora (710 Mb) and C. eugenioides (670 Mb). Both parental species diverged recently (< 4.2Mya) and their genomes are highly homologous. To facilitate assembly, a dihaploid plant was chosen for sequencing. Initial genome assembly attempts with short read data produced an assembly covering 1,031 Mb of the C. arabica genome with a contig L50 of 9kb. By implementation of long read…
Single Molecule Real-Time (SMRT) Sequencing was used to generate long reads for whole genome shotgun sequencing of the genome of the`alala (Hawaiian crow). The ‘alala is endemic to Hawaii, and the only surviving lineage of the crow family, Corvidae, in the Hawaiian Islands. The population declined to less than 20 individuals in the 1990s, and today this charismatic species is extinct in the wild. Currently existing in only two captive breeding facilities, reintroduction of the ‘alala is scheduled to begin in the Fall of 2016. Reintroduction efforts will be assisted by information from the ‘alala genome generated and assembled by…
The complex immune regions of the genome, including MHC and KIR, contain large copy number variants (CNVs), a high density of genes, hyper-polymorphic gene alleles, and conserved extended haplotypes (CEH) with enormous linkage disequilibrium (LDs). This level of complexity and inherent biases of short-read sequencing make it challenging for extracting immune region haplotype information from reference-reliant, shotgun sequencing and GWAS methods. As NGS based genome and exome sequencing and SNP arrays have become a routine for population studies, numerous efforts are being made for developing software to extract and or impute the immune gene information from these datasets. Despite these…
Goats are specialized in dairy, meat and fiber production, being adapted to a wide range of environmental conditions and having a large economic impact in developing countries. In the last years, there have been dramatic advances in the knowledge of the structure and diversity of the goat genome/transcriptome and in the development of genomic tools, rapidly narrowing the gap between goat and related species such as cattle and sheep. Major advances are: 1) publication of a de novo goat genome reference sequence; 2) Development of whole genome high density RH maps, and; 3) Design of a commercial 50K SNP array.…