by Dr. Pandurang Kolekar, Bioinformatics Engineer, Strand Life Sciences

Abstract:

Unique Molecular Identifiers (UMIs) are short random nucleotide sequences that are increasingly being used in high-throughput sequencing experiments. In this webinar, we will highlight the UMI-friendly features of Strand NGS v3.1 including support for handling well known and customised UMI libraries, QC metrics, consensus alignment, UMI-based family size filters for read list, genome browser enabled with UMI-specific features and filters, UMI-aware variant calling parameters, and exporting UMI-tagged aligned samples. These all features together empower users to harness the potential of UMI-tagged NGS data for deeper insights. A case study demonstrating application of these UMI-based features in Strand NGS for low frequency variant calling in cfDNA sample will be presented.

UMI-tagged NGS libraries allow, ultra-sensitive detection of low frequency variants from liquid biopsy samples using DNA-Seq and accurate quantification of transcript-level expression using RNA-Seq. The recent release of Strand NGS v3.1, is equipped with the necessary features to efficiently analyse UMI-tagged NGS data helping researchers and labs involved in rare variant calling like in cfDNA based cancer diagnostics, and accurate transcript quantification with RNA-Seq.

Webinar Details:

Session 1: 13 Dec 2017, 2:30 PM IST
Session 2: 13 Dec 2017, 9:30 PM IST

Register here: http://www.strand-ngs.com/webinar_registration

Address of the bookmark: http://www.sthda.com/english/wiki/rna-seq-differential-expression-work-flow-using-deseq2

What Are Kallisto and Salmon?

At their core, both Kallisto and Salmon are tools for quantifying transcript abundance from RNA-Seq reads. They bypass traditional alignment-based methods, replacing them with pseudoalignment or quasi-mapping, which drastically speeds up the process.

• Kallisto was developed by Lior Pachter’s lab and introduced the concept of pseudoalignment using a de Bruijn graph.
• Salmon, developed by Rob Patro’s group, builds on this idea with quasi-mapping and offers additional features like advanced bias correction.

Head-to-Head Comparison

1. Algorithm

• Kallisto uses pseudoalignment, focusing on matching k-mers from reads to a transcriptome index.
• Salmon uses quasi-mapping, which adds more flexibility and can also work with aligned reads (BAM files).

2. Input and Flexibility

• Kallisto works with raw FASTQ reads and requires a custom transcriptome index.
• Salmon accepts FASTQ or pre-aligned BAM files, giving you more workflow options.

3. Bias Correction

One of Salmon’s major advantages is its sophisticated bias correction system. It corrects for:

• Sequence-specific bias
• Positional bias
• GC-content bias

Kallisto offers basic sequence bias correction but lacks the comprehensive models found in Salmon.

4. Speed and Resources

• Kallisto is blazing fast and slightly more memory-efficient.
• Salmon is still very fast, but the added features can come at a small computational cost.

5. Output and Downstream Analysis

• Both tools provide transcript-level quantifications and support bootstrapping for variance estimation.
• Salmon can also summarize counts at the gene level if provided with a mapping file (--geneMap).
• Kallisto integrates seamlessly with Sleuth for differential expression analysis.
• Salmon works well with tximport, DESeq2, edgeR, and other Bioconductor tools.

Choosing the Right Tool

Example Command Lines

Kallisto (paired-end):

kallisto quant -i transcriptome.idx -o output -b 100 sample_R1.fastq sample_R2.fastq

Salmon (paired-end, bias correction):

salmon quant -i salmon_index -l A -1 sample_R1.fastq -2 sample_R2.fastq \
  -p 8 --validateMappings --seqBias --gcBias -o output

Conclusion

Both Kallisto and Salmon are exceptional tools that have transformed RNA-Seq analysis. Your choice largely depends on your priorities—whether it's speed, accuracy, flexibility, or compatibility with downstream tools.

For many users, Salmon offers a more complete and flexible solution, especially when bias correction and gene-level outputs are essential. However, Kallisto remains a favorite for quick, accurate quantification, especially when paired with the Sleuth pipeline.

.NET Bio

http://blogs.msdn.com/b/msr_er/archive/2011/10/18/microsoft-biology-foundation-evolves-into-new-toolkit-net-bio.aspx

A language-neutral bioinformatics toolkit built using the Microsoft 4.0 .NET Framework to help developers, researchers, and scientists.

AMPHORA ("AutoMated Phylogenomic infeRence Application")

http://wolbachia.biology.virginia.edu/WuLab/Software.html

Metagenomics analysis software

Anduril

http://www.anduril.org/anduril/site/

Component-based workflow framework for data analysis

Armadillo workflow platform

Tool for designing and executing phylogenetic workflows

AutoDock

http://autodock.scripps.edu/

suite of automated docking tools

Biochemical Algorithms Library (BALL)

http://www.ball-project.org/

C++ library and framework for molecular modeling and visualization designed for rapid prototyping

Bio4j

http://bio4j.com/

Bio4j is a bioinformatics platform and graph based database built around most data available in UniProt KB(Swiss-Prot + TrEMBL), Gene Ontology (GO), UniRef (50,90,100), RefSeq, NCBI taxonomy, and Expasy Enzyme DB

Bioclipse

www.bioclipse.net

Visual platform for chemo- and bioinformatics based on the Eclipse Rich Client Platform (RCP).

Bioconductor

http://www.bioconductor.org/

R (programming language) language toolkit

Bioinformatics Learning Tutorial (BLT)

http://sourceforge.net/projects/biotutorial/

Educational interactive tutorials and 3D animations for Replication, Transcription, and Translation

BioHaskell

http://biohaskell.org/

Haskell (programming language)

BioJava

http://biojava.org/wiki/Main_Page

Java (programming language)

BioMOBY

http://biomoby.org/

registry of web services

BioPerl

http://www.bioperl.org/wiki/Main_Page

Perl language toolkit

BioPHP

http://www.biophp.org/

PHP language toolkit

Biopython

http://biopython.org/wiki/Main_Page

Python language toolkit

BioRails

https://github.com/biorails

a data management system designed to support researchers in drug discovery

BioRuby

http://bioruby.org/

Ruby language toolkit

BioSmalltalk

https://code.google.com/p/biosmalltalk/

Smalltalk language toolkit

BioUno

http://www.biouno.org/

BioUno is a project that applies Continuous Integration tools and techniques in Bioinformatics. It uses Jenkins and its plug-in API to create biology workflows and manage computer clusters.

caCORE

ontologic representation environment

caArray

https://cabig-stage.nci.nih.gov/community/tools/caArray

ontologic representation environment

EMBOSS

http://emboss.sourceforge.net/

Suite of packages for sequencing, searching, etc.

Gaggle

https://www.gaggle.net/

A framework for interoperability between systems biology software

Galaxy

http://galaxyproject.org/

Scientific workflow and data integration system

GenePattern

http://www.broadinstitute.org/cancer/software/genepattern/

Scientific workflow system that provides access to more than 150 genomic analysis tools

GeWorkbench

http://wiki.c2b2.columbia.edu/workbench/index.php/Home

Genomic data integration platform

GMOD

http://www.gmod.org/wiki/Main_Page

Toolkit for addressing many common challenges at biological databases.

GeneProf

http://www.geneprof.org/GeneProf/

A web-based, bioinformatics software suite for the analysis of functional genomics experiments, e.g. RNA-seq or ChIP-seq.

GeneTalk

http://www.gene-talk.de/

Tool for filtering sequence variants in VCF files. Network for scientists and clinicians for expertise and knowledge exchange. Database of annotations aboute sequence variants with clinically relevant information.

GenGIS

http://kiwi.cs.dal.ca/GenGIS/Main_Page

Application that allows users to combine digital map data with information about biological sequences collected from the environment.

GenomeSpace

http://www.genomespace.org/

Centralized web application that provides data format transformations and facilitates connections with other bioinformatics tools

GENtle

http://directory.fsf.org/wiki/GENtle

An equivalent to the proprietary Vector NTI, a tool to analyze and edit DNA sequence files

Integrated Genome Browser

http://bioviz.org/igb/

Java-based desktop genome browser

Integrative Genomics Viewer (IGV)

http://www.broadinstitute.org/igv/

High-performance desktop tool for interactive visual exploration of diverse genomic data

IntAct

http://www.ebi.ac.uk/intact/

molecular interaction database

InterMine

http://intermine.github.io/intermine.org/

Extensive data warehouse system for the analysis and integration of biological datasets

Java Treeview

http://jtreeview.sourceforge.net/

microarray data viewer

LabKey Server

http://labkey.com/

platform for integrating, analyzing and sharing data

OpenClinica

https://www.openclinica.com/

software for capturing and managing data in clinical trials

PromKappa

http://xbioinformatics.wordpress.com/tag/promkappa/

PromKappa (Promoter analysis by Kappa) software program used for promoter pattern generation and promoter analysis.

MeV: Multi-Experiment Viewer

http://www.tm4.org/mev.html

a desktop application for the analysis, visualization and data-mining of large-scale genomic data

PathVisio

http://www.pathvisio.org/

a desktop software for drawing, analysis and visualization of biological pathways

REDCRAFT

software for determining tertiary protein structure given assigned Residual Dipolar Coupling data

SAM Tools

Data format (SAM) and accompanying tool suite, for storing large nucleotide sequence alignments

Staden Package

Sequence assembly, editing and analysis, primarily consisting of gap4, gap5 and spin.

STAMP

Software package for analyzing metagenomic profiles that promotes ‘best practices’ in choosing appropriate statistical techniques and reporting results.

supraHex

An open-source R/Bioconductor package for omics data analysis using a supra-hexagonal map

Taverna workbench

Tool for designing and executing workflows

TGAC Browser

Genome Browser, visualisation solutions for big data in the genomic era

T-REX WebServer

Bioinformatics and phylogenetics webserver (NJ, PhyML, RAxML, MAFFT, MUSCLE, Newick viewer, Horizontal gene transfer detection, Reticulograms, Substitution models)

UGENE

integrated bioinformatics tools

Visomics

bioinformatics tools for omics data

Genome Analysis Toolkit 1.0 (GATK 1.0)

a software package to analyse next-generation resequencing data

Address of the bookmark: http://pevsnerlab.kennedykrieger.org/php/?q=software

(1) they enable exploration of hypotheses, and as such, have become invaluable means to guide research;

(2) they are unique approaches to integrate (in the literal term of the word) biological knowledge, in the form of experimental results; and

(3) they enable connecting biology with other fields of study ranging from physiology to genomics;

This blog, and this software list, is intended to guide the potential user of simulation models.
It is not, in any way, meant to be comprehensive on the very diverse simulation tools that already exist, but focuses on mechanistic, dynamic models. Similarly, it is not meant to provide any coverage of the breadth of applications; however, for interested readers, we provide references to use as a possible starting point.

Simulation models are meant to answer questions which scientists have in a dynamic, quantitative, and often, a pictorial way. Much of the bioinformatics research and its applications, in particular, involve a large number of components, actors, and factors. Assembling these in a coherent framework may seem a daunting task, especially for beginners, and can lead to confusion, even for experienced scientists, especially if the objectives of such an exercise are not well defined. Followings are the list of tools bioinformatician may use to analyze and provide answers to complex biological mechanisms and related problems.

In the mid 1960's scientists discovered that many genomes contain stretches of highly repetitive DNA sequences ( see Reassociation Kinetics Experiments, and C-Value Paradox ). These sequences were later characterized and placed into five categories:

Simple Repeats - Duplications of simple sets of DNA bases (typically 1-5bp) such as A, CA, CGG etc.
Tandem Repeats - Typically found at the centromeres and telomeres of chromosomes these are duplications of more complex 100-200 base sequences.
Segmental Duplications - Large blocks of 10-300 kilobases which are that have been copied to another region of the genome.
Interspersed Repeats
Processed Pseudogenes, Retrotranscripts, SINES - Non-functional copies of RNA genes which have been reintegrated into the genome with the assitance of a reverse transcriptase.
DNA Transposons
Retrovirus Retrotransposons
Non-Retrovirus Retrotransposons ( LINES )

Currently up to 50% of the human genome is repetitive in nature and as improvements are made in detection methods this number is expected to increase.

On the other hand; In genetics, the term palindrome refers to a sequence of nucleotides along a DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) strand that contains the same series of nitrogenous bases regardless from which direction the strand is analyzed. Akin to a language palindrome—wherein a word or phrase is spelled the same left-to-right as right-to-left (e.g., the word RADAR or the phrase "able was I ere I saw elba")—with genetic palindromes it does not matter whether the nucleic acid strand is read starting from the 3' (three prime) end or the 5' (five prime) end of the strand.

Recent research on palindromes centers on understanding palindrome formation during gene amplification. Other studies have attempted to relate palindrome formation to molecular mechanisms involved in double stranded breaks and in the formation of inverted repeats. Assisted by high speed computers, other groups of scientists link palindrome formation to the conservation of genetic information.

Related to the direction of transcription by RNA polymerase, DNA strands have upstream and downstream terminus defined by differing chemical groups at each end. The ends of each strand of DNA or RNA are termed the 5' (phosphate bound to the 5' position carbon) and 3' (phosphate bound to the 3' carbon) ends to indicate a polarity within the molecule. Using the letters A, T, C, G, to represent the nitrogenous bases adenine, thymine, cytosine, and guanine found in DNA, and the letters A, U, C, G to represent the nitrogenous bases adenine, uracil, cytosine, guanine found in RNA (Note that uracil in RNA replaces the thymine found in DNA), geneticists usually represent DNA by a series of base codes (e.g., 5' AATCGGATTGCA 3'). The base codes are usually arranged from the 5' end to the 3' end.

Because of specific base pairing in DNA (i.e., adenine (A) always bonds with (thymine (T) and cytosine (C) always bonds with guanine (G)) the complimentary stand to the sequence 5' AATCGGATTGCA 3' would be 3' TTAGCCTAACGT 5'.

With palindromes the sequences on the complimentary strands read the same in either direction. For example, a sequence of 5' GAATTC3' on one strand would be complimented by a 3' CTTAAG 5' strand. In either case, when either strand is read from the 5' prime end the sequence is GAATTC. Another example of a palindrome would be the sequence 5' CGAAGC 3' that, when reversed, still reads CGAAGC.

Palindromes are important sequences within nucleic acids. Often they are the site of binding for specific enzymes (e.g., restriction endobucleases) designed to cut the DNA strands at specific locations (i.e., at palindromes).

Palindromes may arise from brakeage and chromosomal inversions that form inverted repeats that compliment each other. When a palindrome results from an inversion, it is often referred to as an inverted repeat. For example, the sequence 5' CGAAGC 3', if inverted (reversed 180°), still reads CGAAGC.

The European Molecular Biology Open Software Suite (EMBOSS) includes some basic tools for finding tandem repeats and inverted repeats (see B.6.22. Applications in group Nucleic:repeats). There are many on-line services providing the EMBOSS tools, for example:

• Wageningen Bioinformatics Webportal EMBOSS explorer
• Mobyle@Pasteur
• Soaplab2 Web Services at Vital-IT

For more sophisticated repeat finding you will want to look at tools using Repbase for example:

• CENSOR
  • CENSOR@GIRI
  • CENSOR@EMBL-EBI
• RepeatMasker
• MUMmer (scan_for_match)
• Emboss Palindrome

Other nucleotide repeat finding methods found by a couple of web searches:

• Tandem Repeats Finder
• RECON
• RepeatRunner
• REPuter
• Imperfect Microsatellite Extractor (IMEx)
• Spectral Repeat Finder (SRF)
• REPFIND
• CRISPRfinder
• GrailEXP
• CONREPP
• find_palindromes
• Palindrome
• EMBOSS Palindrome
• Palindrome Search

Currently CSBB provides 13 modules focused on analytical tasks like performing upper-quantile normalization on expression data or convert genome wide gene expression to z-scores when comparing expression data from different platforms.

More at https://github.com/skygenomics/CSBB-v1.0

Address of the bookmark: https://github.com/skygenomics/CSBB-v1.0

Address of the bookmark: http://engr.case.edu/li_jing/papers/00798gpattern.pdf

With Single Molecule, Real-Time (SMRT) Sequencing, you can access structural variations having a broad range of sizes, types, and GC content with the ability to:

• Uncover missing heritability linked to structural variation
• Unambiguously identify genomic context and variant breakpoints at the sequence level to unravel the genetic etiology of disease
• Resolve structural variation across the complete size spectrum with basepair resolution

Following are the SV tools, which can assist you to achieve your goal.

Sniffles: Structural variation caller using third generation sequencing

Sniffles is a structural variation caller using third generation sequencing (PacBio or Oxford Nanopore). It detects all types of SVs using evidence from split-read alignments, high-mismatch regions, and coverage analysis. Please note the current version of Sniffles requires sorted output from BWA-MEM (use -M and -x parameter) or NGM-LR with the optional SAM attributes enabled! 

More at https://github.com/fritzsedlazeck/Sniffles

MultiBreak-SV: It identifies structural variants from next-generation paired end data, third-generation long read data, or data from a combination of sequencing platforms.

There are two pieces of software in this release: (1) a pre-processor that takes machineformat (.m5) BLASR files, and (2) MultiBreak-SV. For installation and usage instructions, see doc/MultiBreakSV-Manual.txt.

More at https://github.com/raphael-group/multibreak-sv

Parliament: A Structural Variation Tool. Why ask a single sv-detection approach to find every variant when you can have a parliament of tools deciding?

Publication about the algorithm and “…the first long-read characterization of structural variation in a diploid human personal genome…” (HS1011) - “Assessing structural variation in a personal genome—towards a human reference diploid genome”

More at https://sourceforge.net/projects/parliamentsv/

https://www.dnanexus.com/papers/Parliament_Info_Sheet.pdf

PBHoney: the structural variation discovery tool 

PBHoney is an implementation of two variant-identification approaches designed to exploit the high mappability of long reads (i.e., greater than 10,000 bp). PBHoney considers both intra-read discordance and soft-clipped tails of long reads to identify structural variants.

Read The Paper http://www.biomedcentral.com/1471-2105/15/180/abstract

More at https://sourceforge.net/projects/pb-jelly/

SMRT-SV: Structural variant and indel caller for PacBio reads

Structural variant (SV) and indel caller for PacBio reads based on methods from Chaisson et al. 2014.

SMRT-SV provides an official software package for tools described in Chaisson et al. 2014 and adds several key features including the following.

• Unified variant calling user interface with built-in cluster compute support
• Small indel calling (2-49 bp)
• Improved inversion calling (screenInversions)
• Quality metric for SV calls based on number of local assemblies supporting each call
• Higher sensitivity for SV calls using tiled local assemblies across the entire genome instead of "signature" regions
• Genotyping of SVs with Illumina paired-end reads from WGS samples

More at https://github.com/EichlerLab/pacbio_variant_caller