Difference between revisions of "SequencingFormats"

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These files are created only on request. They have 4 columns:
 
These files are created only on request. They have 4 columns:
  
Column 1 - Sequence
+
Column 1 - Sequence<br>
Column 2 - Number of occurrences of the sequence in column 1 BEFORE filtering
+
Column 2 - Number of occurrences of the sequence in column 1 BEFORE filtering<br>
Column 3 - Does the sequence have the 3' adaptor [1 = yes, 0 = No]
+
Column 3 - Does the sequence have the 3' adaptor [1 = yes, 0 = No]<br>
Column 4 - Number of occurrences of the sequence in column 1 AFTER filtering
+
Column 4 - Number of occurrences of the sequence in column 1 AFTER filtering<br>
  
 
== ELAND Alignment Files ==
 
== ELAND Alignment Files ==

Revision as of 14:33, 11 January 2011

We typically provide the following files/formats as part of a typical data package for HiSeq as well as Genome Analyzer Sequencing Data.

FASTQ Files (Quality Score Files)

This file format is used frequently at the Sanger Institute to bundle a sequence and its quality data. You will find these files in the "QualityScore" folder of the dataset.

A Illumina FASTQ file normally uses four lines per sequence:

Line 1 - begins with a '@' character and is followed by a sequence identifier
Line 2 - the sequence
Line 3 - begins with a '+' character and is optionally followed by the same sequence identifier
Line 4 - the quality values for each base in the sequence in Line 2


An Example:
@WICMT-SOLEXA_0043:7:1:1500:1199#0/1;1
CTCTGCTGTCTCTTGTGTAAGAAGANANNNCNTTCT
+WICMT-SOLEXA_0043:7:1:1500:1199#0/1;1
fffffffRcfad[ddffa]faaaaBBBBBBBBBBBB


The sequence identifier in the above example is "WICMT-SOLEXA_0043:7:1:1500:1199#0/1;1". Please note that the last 2 characters i.e. ";1" may only be found in datasets sequenced by us because we do not remove the filtered reads but indicate them with a 1 (not filtered i.e. good) or 0 (filtered i.e. bad). Please refer to the FAQ's for information on filtering criteria and what it means.

WICMT-SOLEXAInstrument name
0043A unique random string for the whole run (pretty much meaningless)
7flowcell lane
1tile number within the flowcell lane
1500'x'-coordinate of the cluster within the tile
1199'y'-coordinate of the cluster within the tile
#0index number for a multiplexed sample (0 for no indexing)
/1the member of a pair, /1 or /2 (paired-end or mate-pair reads only)
;1Read was not filtered This bit of information is typically not present in FASTQ files created by Illumina pipeline

Technical-Analysis Files

This file is a summary of the alignment results. Please refer to the QC section for more information about this file.

You will only receive this file if a genome alignment was requested.

QC_Report Files

This file summarizes the quality scores (overall as well as per cycle), number of reads and how many were filtered, number of sequences with adaptors and at what position/cycle the adaptor starts as well as the base composition for the entire lane on a cycle by cycles bases for the filtered and unfiltered sets.

Please refer to the QC section for details.

Tag Count Files

These files are created only on request. They have 4 columns:

Column 1 - Sequence
Column 2 - Number of occurrences of the sequence in column 1 BEFORE filtering
Column 3 - Does the sequence have the 3' adaptor [1 = yes, 0 = No]
Column 4 - Number of occurrences of the sequence in column 1 AFTER filtering

ELAND Alignment Files

These files are created if alignments are requested. They can be found in the "Eland_Results_Extended" folder.

The current file naming convention is ss_<LANE>_eland_extended_<GENOME>_<SEEDLENGTH>-<READLENGTH>.txt.

Since the alignment program has been evolving, we have had different formats at different time points. Please refer to this page for the different formats handed out by GTC - http://jura.wi.mit.edu/genomecorewiki/index.php/AlignmentFormat

YLF (Young Lab Format) Files

These files are created on request only. The can be found in the "Eland_Results_Extended" folder along with the alignment results.

UCSC WIG Format Files

These are files in a wig format that can be uploaded directly to the UCSC browser for data visualization. They are created only on request and can be found in the "Analysis" Folder.

Other Files

Depending on the level of collaboration and analysis performed, all other file formats can be found in the "Analysis" folder. These can include normalized counts for each mRNA, peak calls using MACS, miRNA counts, SAM/BAM files etc.