Presentation on theme: "NGS Bioinformatics Workshop 2.1 Tutorial – Next Generation Sequencing and Sequence Assembly Algorithms May 3rd, 2012 IRMACS 10900 Facilitator: Richard."— Presentation transcript:
NGS Bioinformatics Workshop 2.1 Tutorial – Next Generation Sequencing and Sequence Assembly Algorithms May 3rd, 2012 IRMACS Facilitator: Richard Bruskiewich Adjunct Professor, MBB
Agenda Data format review (and some associated tools) Revisit Galaxy Revisit data visualization
FASTQ FASTQ – FASTA “with an attitude” (embedded quality scores). Originally developed at the Sanger to couple (Phred) quality data with sequence, it is now common to specify raw read output data from NGS machines in this format. Various flavors: fastq-sanger fastq-illumina fastq-solexa Differing in the format of the sequence identifier and in the valid range of quality scores. See: /2009/12/16/nar.gkp1137.full “…the Sanger version of the FASTQ format has found the broadest acceptance, supported by many assembly and read mapping tools …Therefore, most users will do this conversion very early in their GTTGCTTCTGGCGTGGGTGGGGGGG +EAS54_6_R1_2_1_443_348 *-+*''))**55CCF>>>>>>CCCC
SAM/BAM SAM– a tab-delimited text file that contains a compact and index-able representation of nucleotide sequence alignments BAM – binary version of SAM (preferred by IGV) I/O format of several NGS tools, see: See also: Li H.*, Handsaker B.*, Wysoker A., Fennell T., Ruan J., Homer N., Marth G., Abecasis G., Durbin R. and 1000 Genome Project Data Processing Subgroup (2009) The Sequence alignment/map (SAM) format and SAMtools. Bioinformatics, 25,
The Picard command-line tools are packaged as executable jar files. They require Java 1.6. They can be invoked as follows: java jvm-args -jar PicardCommand.jar OPTION1=value1 OPTION2=value2... Most of the commands are designed to run in 2GB of JVM, so the JVM argument - Xmx2g is recommended.
Getting & Running Picard… Obtain archive using project “Download” link Extract zip file to sensible location Ensure that you have Java 6 on your machine Run from command shell as indicated
Linux, MacOSX or Unix only
Visualization of NGS Data - Standalone
Visualization of NGS Data – Web Site
GALAXY REVISITED 2.1 Next Generation Sequencing and Sequence Assembly Algorithms
Learning about Galaxy Extensive web resources available: Getting started: “Galaxy 101” Other screencasts Information pages about dataset management, tool usage and data visualization Published pages/protocols: https://main.g2.bx.psu.edu/page/list_published
Logging into WestGrid https://joffre.westgrid.ca/galaxy/ Accessing the Westgrid Galaxy instance Use your Westgrid ID ( name to log into Joffre, e.g. if your is your server access id is ‘rbruskie’, and use your WestGrid password Logging into the Galaxy instance Once into Galaxy, you need to register (initially) or log in (if already registered) using your username (your full , e.g. and (important!) use your WestGrid password as the Galaxy password
Small issue for access through IE?
We will run through “Galaxy 101” https://main.g2.bx.psu.edu/galaxy101 Try it! Ask questions along the way….
Some sensible steps for processing NGS data Obtain the data (i.e. upload to Galaxy) Assess quality of read data Convert reads to convenient form (fastq?) Filter out questionable data: low quality, vector Process to integrate de novo assembly: Allpaths, ABySS, Velvet, SOAPdenovo, etc., or… Map onto reference: SAM, Bowtie, MAQ, etc. Clean up and visualize