BOL: Related items

BLAST+ 2.10.0 released

Jit — Wed, 18 Dec 2019 20:44:11 -0600

The BLAST+ 2.10.0 release is now available from at FTP site. The new version offers the following improvements:

updated composition-based statistics for protein-protein (including translated BLAST) comparisons to provide stable results when you request fewer than the default number of results
an experimental Adaptive Composition Based Statistics option that increases the likelihood of finding novel results. To enable this option set the environment variable ADAPTIVE_CBS to 1. We welcome your feedback on this new option.

See the release notes for details on more improvements and bug fixes with this release.

BLAST+ is also available in docker, please read more for details.

The new version fully supports the version 5 (v5) databases with built in taxonomy and other improvements. For more information on v5 databases (download), see the previous NCBI Insights article and the recording of our webinar. If you are still using the older version 4 (v4) databases, we recommend you begin using the v5 version as soon as possible. We will discontinue updates to the older v4 databases in early 2020.

BLAST+ Team

NCBI BLAST have added new columns to the Descriptions

Neel — Tue, 01 Dec 2020 09:56:07 -0600

NCBI BLAST have added new columns to the Descriptions Table for web BLAST output. The new columns are Scientific Name, Common Name, Taxid, and Accession Length. Common Name and Accession Length are now part of the default display. You can click 'Select columns' or 'Manage columns' to add or remove columns from the display Your preferences will be saved for your next visit to BLAST, and when you download your results, whatever columns you have displayed will be saved. See the NCBI Insights post (https://go.usa.gov/x7fPE) for more details.

Alignment of closely related whole genomes/scaffolds

Rahul Nayak — Fri, 29 Jan 2016 10:37:27 -0600

With the relative ease and low cost of current generation sequencing technologies has led to a dramatic increase in the number of sequenced genomes for species across the tree of life. This increasing volume of data requires tools that can quickly compare multiple whole-genome sequences, millions of base pairs in length, to aid in the study of populations, pan-genomes, and genome evolution.This bookmaks have been created to report new tools for whole genome alignments.

Please report new whole genome alignment tools under comment sections.

Address of the bookmark: http://www.cs.utoronto.ca/~brudno/721.full.pdf

Understanding reads mapping and flags !

Jit — Thu, 25 Apr 2019 09:06:20 -0500

Linear Alignment: An alignment of a read to a single reference sequence that may include insertions, deletions, skips and clipping, but may not include direction changes (i.e. one portion of the alignment on forward strand and another portion of alignment on reverse strand).

Chimeric Alignment: An alignment of a read that cannot be represented as a linear alignment. Typically, one of the linear alignments in a chimeric alignment is considered the “representative” alignment, and the others are called “supplementary” and are distinguished by the supplementary alignment flag.

Chimeric reads are indicative of structural variation in DNA-seq and it may indicate the presence of chimeric genes in RNA-seq.

In short, chimeric reads can be split in to two or more parts, each part would be mapped to reference(it’s not hard-clipped), the total length of the mapped part is longger than read length.

Representative alignment: A chimeric alignment that is represented as a set of linear alignments that do not have large overlaps typically has one linear alignment that is considered the representative alignment.

One read can align to multiple positions, we can find one alignmnet position which sequence do not have large overlaps, it called representative alighment, for other alignment positions, we called them supplementary alignment.

It seems that GATK can realignment those representative reads to the correctly position via RealignerTargetCreator and IndelRealigner. (WARNING: I am not quite sure if I understand this correctly. If someone could help me, please leave me a message below, thanks, thanks.)

Supplementary Alignment: A chimeric reads but not a representative reads.

Primary Alignment and Secondary Alignment: A read may map ambiguously to multiple locations, e.g. due to repeats. Only one of the multiple read alignments is considered primary, and this decision may be arbitrary. All other alignments have the secondary alignment flag.

Many-to-many pairwise alignments of two sequence sets

Poonam Mahapatra — Tue, 19 Jun 2018 08:34:15 -0500

needleall reads a set of input sequences and compares them all to one or more sequences, writing their optimal global sequence alignments to file. It uses the Needleman-Wunsch alignment algorithm to find the optimum alignment (including gaps) of two sequences along their entire length. The algorithm uses a dynamic programming method to ensure the alignment is optimum, by exploring all possible alignments and choosing the best. A scoring matrix is read that contains values for every possible residue or nucleotide match. Needleall finds the alignment with the maximum possible score where the score of an alignment is equal to the sum of the matches taken from the scoring matrix, minus penalties arising from opening and extending gaps in the aligned sequences. The substitution matrix and gap opening and extension penalties are user-specified.

Address of the bookmark: http://emboss.sourceforge.net/apps/release/6.6/emboss/apps/needleall.html

BamView: a free interactive display of read alignments in BAM data files

Neel — Fri, 09 Nov 2018 13:43:22 -0600

To run the application on UNIX from the downloaded jar file run the UNIX:

java -mx512m -jar BamView.jar

and extra command line options are given when '-h' is used:

java -jar BamView.jar -h

BAM files can be specified on the command line with the '-a' option:

java -mx512m -jar BamView.jar -a pathToFile/sorted.bam

If a BAM filename is not given on the command line BamView will prompt for a file to be entered. The BAM index file should have the same name as the BAM file but with a '.bai' suffix. Multiple BAM files can be loaded and overlaid in the viewer. To make this easier BamView will read in files that contain a list of filenames.

Address of the bookmark: http://bamview.sourceforge.net/

Termal: a fast and interactive terminal-based viewer for multiple sequence alignments

LEGE — Mon, 22 Sep 2025 23:51:02 -0500

termal, a fast, interactive, terminal-based viewer for multiple sequence alignments (MSAs), designed for use on remote systems such as high-performance computing (HPC) clusters.

https://academic.oup.com/bioinformaticsadvances/advance-article/doi/10.1093/bioadv/vbaf208/8257678?login=true

Address of the bookmark: https://github.com/sib-swiss/termal

Demo 4: Using BLAST/BLAT in Ensembl

Tue, 10 Sep 2013 11:54:03 -0500

We demonstrate the BLAST/BLAT tool in Ensembl. Search for a sequence in Ensembl, and identify hits to the genome, or to genes, with this tool.

Genome Workbench 2.10.7

Gudiya Pal — Fri, 01 Jul 2016 12:09:59 -0500

Genome Workbench 2.10.7 is here! New features include added support for local custom BLAST databases and improvements to Tree View.

For the full list of features, improvements and fixes, see the release notes:https://ncbi.nlm.nih.gov/tools/gbench/releasenotes

New Features

BLAST Tool: added support for local custom BLAST databases
Graphical Sequence View: added log scaling option for graph tracks
Generic Table View: new tutorial added

Bug Fixes and Improvements

Project Tree View: Genomic Collections/Assemblies now show accessions, not just names
Tree View: layout updated to better accommodate nodes of different sizes
Table Import Dialog (MacOS): fixed issue with table visibility
Fixed bug where different molecules IDs in GenBank could resolve to the same sequence
Graphical Sequence View: fixed issue where sequence track was not shown for some sequences
Graphical Sequence View: fixed protein coloration methods
Graphical Sequence View: improved rendering of Markers to better indicate boundaries and produce higher quality PDF images
Create Gene Model tool: fixed scenario when gene model tool failed with local sequences
Search View: ORF Finder – fixed incorrect protein lengths
Fixed bug with not opening project file (.gbp) on a click
Fixed issues in GVF import
Fixed BLAST Search tool against NCBI databases not working
Fixed tblastn (protein BLAST) not working in standalone mode
Fixed GTF export failure

DIAMOND

Jit — Thu, 27 Apr 2017 04:21:54 -0500

DIAMOND is a sequence aligner for protein and translated DNA searches and functions as a drop-in replacement for the NCBI BLAST software tools. It is suitable for protein-protein search as well as DNA-protein search on short reads and longer sequences including contigs and assemblies, providing a speedup of BLAST ranging up to x20,000.

More at file:///home/urbe/Downloads/diamond_manual.pdf

http://www.nature.com/nmeth/journal/v12/n1/full/nmeth.3176.html

Address of the bookmark: https://github.com/bbuchfink/diamond