BOL: Related items

HISAT2: a fast and sensitive alignment program for mapping next-generation sequencing reads

Rahul Nayak — Tue, 08 May 2018 04:27:22 -0500

HISAT2 is a fast and sensitive alignment program for mapping next-generation sequencing reads (both DNA and RNA) to a population of human genomes (as well as to a single reference genome). Based on an extension of BWT for graphs [Sirén et al. 2014], we designed and implemented a graph FM index (GFM), an original approach and its first implementation to the best of our knowledge. In addition to using one global GFM index that represents a population of human genomes, HISAT2 uses a large set of small GFM indexes that collectively cover the whole genome (each index representing a genomic region of 56 Kbp, with 55,000 indexes needed to cover the human population). These small indexes (called local indexes), combined with several alignment strategies, enable rapid and accurate alignment of sequencing reads. This new indexing scheme is called a Hierarchical Graph FM index (HGFM).

more at https://ccb.jhu.edu/software/hisat2/index.shtml

Address of the bookmark: https://github.com/infphilo/hisat2

Mulan: Multiple-sequence local alignment and visualization for studying function and evolution

Jit — Fri, 24 Aug 2018 09:50:01 -0500

Mulan: Multiple-sequence local alignment and visualization for studying function and evolution

Mulan (http://mulan.dcode.org/), a novel method and a network server for comparing multiple draft and finished-quality sequences to identify functional elements conserved over evolutionary time. Mulan brings together several novel algorithms: the TBA multi-aligner program for rapid identification of local sequence conservation, and the multiTF program for detecting evolutionarily conserved transcription factor binding sites in multiple alignments. In addition, Mulan supports two-way communication with the GALA database; alignments of multiple species dynamically generated in GALA can be viewed in Mulan, and conserved transcription factor binding sites identified with Mulan/multiTF can be integrated and overlaid with extensive genome annotation data using GALA.

Address of the bookmark: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC540288/

MSAProbs - Parallel and accurate multiple sequence alignment

Neel — Tue, 09 Jul 2019 23:58:44 -0500

MSAProbs is a well-established state-of-the-art multiple sequence alignment algorithm for protein sequences. The design of MSAProbs is based on a combination of pair hidden Markov models and partition functions to calculate posterior probabilities. Assessed using the popular benchmarks: BAliBASE, PREFAB, SABmark and OXBENCH, MSAProbs achieves statistically significant accuracy improvements over the existing top performing aligners, including ClustalW, MAFFT, MUSCLE, ProbCons and Probalign. In addition, MSAProbs is optimized for shared-memory CPUs by employing a multi-threaded design, and further parallelized for distributed-memory systems using MPI to overcome high memory overhead barrier and achieve good parallel and data-size scalability.

Address of the bookmark: http://msaprobs.sourceforge.net/homepage.htm#latest

VG: variation graph data structures, interchange formats, alignment, genotyping, and variant calling methods

Jit — Tue, 28 Jan 2020 03:53:24 -0600

Variation graphs provide a succinct encoding of the sequences of many genomes. A variation graph (in particular as implemented in vg) is composed of:

nodes, which are labeled by sequences and ids
edges, which connect two nodes via either of their respective ends
paths, describe genomes, sequence alignments, and annotations (such as gene models and transcripts) as walks through nodes connected by edges

Address of the bookmark: https://github.com/vgteam/vg

UniAligner: a parameter-free framework for fast sequence alignment

Abhi — Fri, 08 Mar 2024 23:36:12 -0600

UniAligner (formerly, TandemAligner) is the first parameter-free algorithm for sequence alignment that introduces a sequence-dependent alignment scoring that automatically changes for any pair of compared sequences. Classical alignment approaches, such as the Smith-Waterman algorithm, that work well for most sequences, fail to construct biologically adequate alignments of extra-long tandem repeats (ETRs), such as human centromeres and immunoglobulin loci. This limitation was overlooked in the previous studies since the sequences of the centromeres and other ETRs across multiple genomes only became available recently.

More at https://www.nature.com/articles/s41592-023-01970-4

Address of the bookmark: https://github.com/seryrzu/unialigner

Seal: SEquence ALignment evaluation suite

Jit — Wed, 03 Jan 2018 05:05:46 -0600

Seal is a comprehensive sequencing simulation and alignment tool evaluation suite. This software (implemented in Java) provides several utilities that can be used to evaluate alignment algorithms, including:

Reading a pre-existing reference genome from one or more FASTA files.
Alternatively, generating an artificial reference genome based on input parameters (length, repeat count, repeat length, repeat variability rate).
Simulating reads from random locations in the genome based on input parameters of read length, coverage, sequencing error rate, and indel rate.
Applying alignment tools to the genome and the reads through a standardized interface.
Parsing the output of the alignment tool and calculating the number of reads that were correctly or incorrectly mapped.
Computing run times and measures of accuracy.

Seal has interfaces to evaluate the following software packages:

Bowtie
BWA
MAQ
mrFAST
mrsFAST
Novoalign
SHRiMP
SOAPv2

Address of the bookmark: http://compbio.case.edu/seal/

SIMON BOULTON LAB

Tue, 11 Dec 2018 09:01:46 -0600

DNA is quite fragile and easily damaged, both by the normal processes of life at work within our cells and by external agents such as the chemicals in tobacco smoke or ultraviolet (UV) rays from the sun. However, our cells have evolved clever ‘repair kits’ that spot DNA damage and patch it up, helping to protect us against tumours. If these repair kits are faulty or inefficient then mistakes can quickly build up and cause cells to become cancerous.

They are particularly interested in a type of DNA repair known as double-strand break repair, which happens when the DNA molecule has been completely snapped in two. Not only does this happen in normal cells in the body to repair DNA damage, but it also occurs when eggs and sperm are made (known as meiosis) and during the generation of cells in the immune system.

https://www.crick.ac.uk/research/labs/simon-boulton

ChopStitch: exon annotation and splice graph construction using transcriptome assembly and whole genome sequencing data

Rahul Nayak — Tue, 03 Jul 2018 04:14:52 -0500

ChopStitch is a new method for finding putative exons and constructing splice graphs using an assembled transcriptome and whole genome shotgun sequencing (WGSS) data. ChopStitch identifies exon-exon boundaries in de novo assembled RNA-seq data with the help of a Bloom filter that represents the k-mer spectrum of WGSS reads. The algorithm also detects base substitutions in transcript sequences corresponding to sequencing or assembly errors, haplotype variations, or putative RNA editing events. The primary output of our tool is a FASTA file containing putative exons. Further, exon edges are interrogated for alternative exon-exon boundaries to detect transcript isoforms, which are reported as splice graphs in dot output format.

Address of the bookmark: https://github.com/bcgsc/ChopStitch

DUPCAR: Reconstructing Contiguous Ancestral Regions with Duplications

Jit — Mon, 21 May 2018 11:09:02 -0500

we propose a heuristic algorithm, called DUPCAR, for reconstructing ancestral genomic orders with duplications. The method starts from the order of genes in modern genomes and predicts predecessor and successor relationships in the ancestor. Then a greedy algorithm is used to reconstruct the ancestral orders by connecting genes into contiguous regions based on predicted adjacencies. Computer simulation was used to validate the algorithm. We also applied the method to reconstruct the ancestral chromosome X of placental mammals and the ancestral genomes of the ciliate Paramecium tetraurelia.

Address of the bookmark: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3205822/

GenoFig: a user-friendly application for the visualization and comparison of genomic regions

BioStar — Mon, 05 Aug 2024 23:06:58 -0500

Tool for graphical vizualisation of annotated genetic regions, and homologous regions comparison. It is an independent recoding of Easyfig 2 initially developped by at the S. Beatson Lab [https://mjsull.github.io/Easyfig/]

Download the GenoFig source code using the 'Download' button on top of this page. Cloning is currently not available for people not member of the INRAE French Institution. After decompression, open a terminal in the folder containing the decompressed files and run:

conda env create -f extras/requirements.yml
extras/SETUP.sh

Address of the bookmark: https://forgemia.inra.fr/public-pgba/genofig