BOL: Related items

jobTree based python wrapper to run the genome simulation tool suite Evolver

Jit — Fri, 08 Dec 2017 16:26:32 -0600

evolverSimControl (eSC) can be used to simulate multi-chromosome genome evolution on an arbitrary phylogeny (Newick format). In addition to simply running evolver, eSC also automatically creates statistical summaries of the simulation as it runs including text and image files. Also included are convenience scripts to: check on a running simulation and see detailed status and logging information; extract fasta sequence files from the leaf nodes of a completed simulation; extract pairwise multiple alignment files (.maf) from leaf and branch nodes from a completed simulation and with the help of mafJoin, join them together into a single maf covering the entire simulation.

Address of the bookmark: https://github.com/dentearl/evolverSimControl

Oldest Hominin DNA Sequenced

Surajeet — Fri, 27 Dec 2013 19:58:31 -0600

Matthias Meyer and his team from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, have developed new techniques for retrieving and sequencing highly degraded ancient DNA. They then joined forces with Juan-Luis Arsuaga and applied the new techniques to a cave bear from the Sima de los Huesos site. After this success, the researchers sampled two grams of bone powder from a hominin thigh bone from the cave. They extracted its DNA and sequenced the genome of the mitochondria or mtDNA, a small part of the genome that is passed down along the maternal line and occurs in many copies per cell. The researchers then compared this ancient mitochondrial DNA with Neandertals, Denisovans, present-day humans, and apes.

From the missing mutations in the old DNA sequences the researchers calculated that the Sima hominin lived about 400,000 years ago. They also found that it shared a common ancestor with the Denisovans, an extinct archaic group from Asia related to the Neandertals, about 700,000 years ago. "The fact that the mtDNA of the Sima de los Huesos hominin shares a common ancestor with Denisovan rather than Neandertal mtDNAs is unexpected since its skeletal remains carry Neandertal-derived features," says Matthias Meyer. Considering their age and Neandertal-like features, the Sima hominins were likely related to the population ancestral to both Neandertals and Denisovans. Another possibility is that gene flow from yet another group of hominins brought the Denisova-like mtDNA into the Sima hominins or their ancestors.

Reference

http://www.sciencedaily.com/releases/2013/12/131204132018.htm

String graph based genome assembly software and tools !

Rahul Nayak — Tue, 19 Dec 2017 17:17:38 -0600

In graph theory, a string graph is an intersection graph of curves in the plane; each curve is called a "string". String graphs were first proposed by E. W. Myers in a 2005 publication. In recent Genome Research paper describing an innovative approach for assembling large genomes from NGS data caught our attention for several reasons. i) it give different "string graph" prospective of long lasting genome assembly problem ii) the paper is coauthored by Jared Simpson, the developer of ABySS assembler and Richard Durbin. iii) Simpson-Durbin algorithm is that it does not rely on de Bruijn graphs, and instead employs a different graph construction approach called ‘string graph’.

Following are the genome assembly tools based on string graph:

1.SGA (String Graph Assembler) https://github.com/jts/sga

Assembles large genomes from high coverage short read data. SGA is designed as a modular set of programs, which are used to form an assembly pipeline. SGA implements a set of assembly algorithms based on the FM-index. As the FM-index is a compressed data structure, the algorithms are very memory efficient. The SGA assembly has three distinct phases. The first phase corrects base calling errors in the reads. The second phase assembles contigs from the corrected reads. The third phase uses paired end and/or mate pair data to build scaffolds from the contigs. The output of this software is a PDF report that allows the properties of the genome and data quality to be visually explored. By providing more information to the user at the start of an assembly project, this software will help increase awareness of the factors that make a given assembly easy or difficult, assist in the selection of software and parameters and help to troubleshoot an assembly if it runs into problems.

2. SAGE: String-overlap Assembly of GEnomes https://github.com/lucian-ilie/SAGE2

SAGE, for de novo genome assembly. As opposed to most assemblers, which are de Bruijn graph based, SAGE uses the string-overlap graph. SAGE builds upon great existing work on string-overlap graph and maximum likelihood assembly, bringing an important number of new ideas, such as the efficient computation of the transitive reduction of the string overlap graph, the use of (generalized) edge multiplicity statistics for more accurate estimation of read copy counts, and the improved use of mate pairs and min-cost flow for supporting edge merging. The assemblies produced by SAGE for several short and medium-size genomes compared favourably with those of existing leading assemblers.

3. FSG: Fast String Graph

The new integrated assembler has been assessed on a standard benchmark, showing that fast string graph (FSG) is significantly faster than SGA while maintaining a moderate use of main memory, and showing practical advantages in running FSG on multiple threads. Moreover, we have studied the effect of coverage rates on the running times.

4. BASE https://github.com/dhlbh/BASE

It enhances the classic seed-extension approach by indexing the reads efficiently to generate adaptive seeds that have high probability to appear uniquely in the genome. Such seeds form the basis for BASE to build extension trees and then to use reverse validation to remove the branches based on read coverage and paired-end information, resulting in high-quality consensus sequences of reads sharing the seeds. Such consensus sequences are then extended to contigs. BASE is a practically efficient tool for constructing contig, with significant improvement in quality for long NGS reads. It is relatively easy to extend BASE to include scaffolding.

5. Fermi https://github.com/lh3/fermi/

Fermi is a de novo assembler with a particular focus on assembling Illumina short sequence reads from a mammal-sized genome. In addition to the role of a typical assembler, fermi also aims to preserve heterozygotes which are often collapsed by other assemblers. Its ultimate goal is to find a minimal set of unitigs to represent all the information in raw reads.

If you want to learn about String Graph assembler, please read the following papers -

i) The Fragment Assembly String Graph - E. W. Myers

This paper describes the String Graph concept.

ii) Efficient construction of an assembly string graph using the FM-index - Jared T. Simpson and Richard Durbin

This earlier paper from Simpson and Durbin

iii) Efficient de novo assembly of large genomes using compressed data structures - Jared T. Simpson and Richard Durbin

MUMmer4: A fast and versatile genome alignment system

Jit — Sat, 03 Feb 2018 04:59:17 -0600

MUMmer4, a substantially improved version of MUMmer that addresses genome size constraints by changing the 32-bit suffix tree data structure at the core of MUMmer to a 48-bit suffix array, and that offers improved speed through parallel processing of input query sequences. With a theoretical limit on the input size of 141Tbp, MUMmer4 can now work with input sequences of any biologically realistic length. We show that as a result of these enhancements, the nucmer program in MUMmer4 is easily able to handle alignments of large genomes;

Address of the bookmark: https://mummer4.github.io/

The 2014 CeMM PhD Program

Wed, 05 Feb 2014 06:03:15 -0600

For our next PhD Program starting in October 2014 we are looking for exceptionally motivated PhD candidates with a keen interest in genomics and medicine and a strong interest to work in teams.

The 2014 CeMM PhD Program will focus on two thematic areas: INFECTION and CANCER, that are built on the pillars of epigenetics, bioinformatics and systems biology, chemical biology and the mechanism of action of drugs, high-throughput genetics, genomics and proteomics, and molecular and cell biology.

The choice of this strategic focus rests on the synergies between immunology, infection and cancer in pathophysiological and technological terms. It furthermore reflects the strength of the current CeMM faculty, itself built around the historical and contemporary expertise in immunology and cancer of the Medical University of Vienna.

As a CeMM PhD student you will get the chance to work at the cutting edge of interdisciplinary molecular medicine research and be trained by the entire CeMM and associated faculty to become one of the scientists shaping the future of molecular medicine.
Requirements

To be eligible to enroll in the CeMM PhD Program all candidates are required to have a bachelor’s or master’s degree in medicine, biology, chemistry, bioinformatics, mathematics or any scientific/technical, subject-relevant degree. Candidates do not need to have completed their degree at the time of application, however they must have obtained their final degree certificate by mid-September. The working language at CeMM is English, so excellent written and oral communication skills in English are required.
Timeline

Applications open on 20th January and close on 20th March 2014.
Two references are required to be submitted through the online system by 31st March 2014.
All complete candidate applications are reviewed by the CeMM Faculty in early April.
Selected candidates are invited to a Skype panel interview in late April.
Shortlisted candidates are then invited to Vienna in May for a full interview process, including an opportunity to introduce yourself through a presentation and interview rounds, meet research group members, and attend an informal dinner to get to know the Faculty members and learn more about their research.
Positions are offered by CeMM Faculty in June.
Start of PhD Program: 1st October 2014 .

Contact

Binia Maria Günther, BEd BA
Human Resources Manager
bguenther@cemm.oeaw.ac.at

Catherine Lloyd, Ph.D.
PhD and Postdoc Program Manager
clloyd@cemm.oeaw.ac.at

More Info: www.cemm.oeaw.ac.at/phd-program/application/

AlignGraph: algorithm for secondary de novo genome assembly guided by closely related references

Manisha Mishra — Tue, 17 Apr 2018 16:21:20 -0500

AlignGraph is a software that extends and joins contigs or scaffolds by reassembling them with help provided by a reference genome of a closely related organism.

Using AlignGraph

AlignGraph --read1 reads_1.fa --read2 reads_2.fa --contig contigs.fa --genome genome.fa --distanceLow distanceLow --distanceHigh distancehigh --extendedContig extendedContigs.fa --remainingContig remainingContigs.fa [--kMer k --insertVariation insertVariation --coverage coverage --part p --fastMap --ratioCheck --iterativeMap --misassemblyRemoval --resume]

Address of the bookmark: https://github.com/baoe/AlignGraph

JRF @ MANIT

Sun, 02 Feb 2014 03:07:58 -0600

MAULANA AZAD NATIONAL INSTITUTE OF TECHNOLOGY BHOPAL

No. CSE/14/1038

Walk in Interview for the post of JRF under TEQIP-II

SN Department – Qualification Post Graduation – Time

1 Bio-Informatics & Mathematics M.Tech Bio-informatics/M.Sc.* Maths 10.00 AM

2 Biological Sciences M.Sc.* in any branch of Biological Sciences 10.30 AM

3 Chemical Engineering M.Tech Chemical Engineering 11.00 AM

4 Chemistry M.Sc.* Chemistry 11.30 AM

5 Civil Engineering M.Tech Structure/GeoTech. /Water -Resources/Hydraulics/Environment/Transport 12.00 Noon

6 GIS M.Tech GIS/Civil 12.30 PM

7 Computer Science & Engineering M.Tech CSE/Information Security 01.00 PM

8 Electrical Engineering M.Tech Electrical Derives 01.30 PM

9 Electronics & Communication M.Tech Digital Communication 02.00 PM

10 MSME M.Tech Material Science/ Mechanical/Metallurgy 02.30 PM

11 Physics M.Sc.* Physics 03.00 PM

* M.Sc. with NET/GATE qualified

Resume along with one passport size photograph and relevant documents are required at the time of interview

Amount of Fellowship: Rs 18000/-month+ HRA

Duration: 31st Dec 2014 (End of TEQIP-II project)

Date of Interview: 7th February 2014

Venue Institute Committee Room

http://www.manit.ac.in/manitbhopal/Year2014/Recruitment/Advertisement%20JRF.pdf

CrossMap: a program for convenient conversion of genome coordinates

Jit — Thu, 31 May 2018 06:00:47 -0500

CrossMap is a program for convenient conversion of genome coordinates (or annotation files) between different assemblies (such as Human hg18 (NCBI36) <> hg19 (GRCh37), Mouse mm9 (MGSCv37) <> mm10 (GRCm38)). It supports most commonly used file formats including SAM/BAM, Wiggle/BigWig, BED, GFF/GTF, VCF. CrossMap is designed to liftover genome coordinates between assemblies. It’s not a program for aligning sequences to reference genome. We do not recommend using CrossMap to convert genome coordinates between species.

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

Post doc in Computational Genetics and Genomics at CEINGE Biotecnologie Avanzate, Naples, Italy

Tue, 11 Feb 2014 08:06:47 -0600

We are seeking one motivated scientist to analyze genomics and transcriptomics data of a large collection of neuroblastoma tumors. The successful candidate will be part of a team of researchers with extensive expertise in genome cancer study. He/she will be involved in the analysis of DNA-seq, RNA-seq, ChIP-seq data using available methods running in R and UNIX environment.

Qualifications

PhD or Post-Graduated Master degree is required. Successful candidates will have some expertise in data analysis of NGS data by using methods running in R and UNIX environment. Familiarity with genome databases and browsers is required.

Application

Candidates should send a CV and a brief personal statement focusing on their skills and interests related to the research project.

Contacts

Start date: 1° April 2014
Salary on grant: 25,000 euros per year.
Contact Person (Referent): Mario Capasso
Ref. Email: mario.capasso@unina.it and achille.iolascon@unina.it
Tel: +39 081 3737889

assemblytics: delta file to analyze alignments of an assembly to another assembly or a reference genome

Jit — Thu, 14 Jun 2018 07:31:00 -0500

Download and install MUMmer Align your assembly to a reference genome using nucmer (from MUMmer package) $ nucmer -maxmatch -l 100 -c 500 REFERENCE.fa ASSEMBLY.fa -prefix OUT Consult the MUMmer manual if you encounter problems Optional: Gzip the delta file to speed up upload (usually 2-4X faster) $ gzip OUT.delta Then use the OUT.delta.gz file for upload. Upload the .delta or delta.gz file (view example) to Assemblytics Important: Use only contigs rather than scaffolds from the assembly. This will prevent false positives when the number of Ns in the scaffolded sequence does not match perfectly to the distance in the reference. The unique sequence length required represents an anchor for determining if a sequence is unique enough to safely call variants from, which is an alternative to the mapping quality filter for read alignment. http://assemblytics.com/

Address of the bookmark: http://assemblytics.com/