Unconfigured Ad

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • paa6
    Member
    • Feb 2014
    • 68

    #1

    illumina sequencing assembly

    I am trying to do assembly and the file format is .qual format. I have tried geneious and velvet format but they dont support .qual format, so I have tried to convert this file into fasta file and then performing the assembly. Geneious and velvet both accepting the file now but I am getting message that "NO CONTIGS IS FOUND" by geneious and contig file is empty in case of velvet. I dont know where I am doing wrong please reply me...
    Last edited by paa6; 02-03-2014, 04:49 PM.
  • GenoMax
    Senior Member
    • Feb 2008
    • 7142

    #2
    Is this data from Illumina sequencing? Illumina data has been in FASTQ format (with some changes to the way the quality values were encoded) over the years.

    Can you post a small example from a file you are referring to as being of .qual format?

    Comment

    • paa6
      Member
      • Feb 2014
      • 68

      #3
      ACTUALLY MY FILE IS IN .QUAL FORMAT...i guess in this file format sequnce is in numeric format...this is the file i have got from my PI. there is other file also in .sff format but first he wants to assemble .qual format file.

      one thing I have understood while using geneious that u should have forward and reverse reads to perform assembly but in my case I have only one read file so I dont know how to assemble it...

      Comment

      • GenoMax
        Senior Member
        • Feb 2008
        • 7142

        #4
        You appear to have data from a SOLiD sequencer. I have no experience with data from a SOLiD instrument. Hopefully someone else on the forum will step in to help.

        Meanwhile see some past threads related to this topic:

        Discussion of next-gen sequencing related bioinformatics: resources, algorithms, open source efforts, etc
        Last edited by GenoMax; 02-02-2014, 06:46 PM.

        Comment

        • paa6
          Member
          • Feb 2014
          • 68

          #5
          THANK U SO MUCH...but is this mean that my sequence is not illumina sequencing?? then what kind of sequence is this..I mean what should I call it...I am looking for a name..

          Comment

          • sklages
            Senior Member
            • May 2008
            • 628

            #6
            Well, it seems that you have a Roche 454 dataset. The "qual" file is only the quality portion of the dataset (missing the fna = sequence file). The "original" or "raw" file, containing all sequence information is the SFF file you have mentioned.

            So either ask your PI to also provide the corresponding fasta (fna) sequence file or just create your sequence files by yourself from the SFF file using public available tools (sff_extract, SFF Tools from Roche).

            But AFAIR "geneious" can directly import SFF files, which should get the most out of the data (and is probably the safest way).

            Comment

            • GenoMax
              Senior Member
              • Feb 2008
              • 7142

              #7
              I guess this could also be a 454 data set (though why paa6 was not given the *.fna files is a mystery).

              @paa6: In any case you should get additional information about this data set from your supervisor. At the least start with the SFF files and see if Geneious can import them.

              Comment

              • paa6
                Member
                • Feb 2014
                • 68

                #8
                i have only two types of files .sff and .qual format. After reading so much now I am also thinking that this is 454 sequencing files...I have tried to import .sff into geneious but it's showing error message.

                Comment

                • paa6
                  Member
                  • Feb 2014
                  • 68

                  #9
                  this is the msg I am getting...
                  Attached Files

                  Comment

                  • mastal
                    Senior Member
                    • Mar 2009
                    • 666

                    #10
                    Try getting the sequences from the sff file using sff_extract.




                    You can also convert the sff files to a text format, .sff.txt, so then you could have a look
                    at the first few lines to see if the data looks like it is what you expected.

                    I'm not sure if sff_extract or seq_crumbs will do that, though, or if you need the Roche software.

                    Comment

                    • sklages
                      Senior Member
                      • May 2008
                      • 628

                      #11
                      Your dataset seems to be incomplete (missing fna, basic stats) .. ask your PI for information about the data and the complete dataset (fna/qual and sff file(s)).

                      How did you receive your data? USB stick/disk, download?
                      If it is a big SFF file you might want to check MD5 checksums (in case you have downloaded the data).

                      Concerning the error you get during import into geneious you should contact their support team.

                      Comment

                      • paa6
                        Member
                        • Feb 2014
                        • 68

                        #12
                        @mastal I did try to change into .txt but sadly its not responding...not getting open...so I will try ur link...thanks...

                        Comment

                        • paa6
                          Member
                          • Feb 2014
                          • 68

                          #13
                          @sklaegs I got my data from usb and that was given by my supervisor...

                          Comment

                          • paa6
                            Member
                            • Feb 2014
                            • 68

                            #14
                            @skladge can u provide me any research paper mentioning that to assembl the 454 u need all these formats...so that I can show him proof. He was telling me that .qual is an Illumina sequencing file and .sff is 454 sequencing. So, obviously if i will try to explain him that they both are the same file of 454 sequencing and I need additional files too...so, I need to show him research paper...

                            Comment

                            • sklages
                              Senior Member
                              • May 2008
                              • 628

                              #15
                              Originally posted by paa6 View Post
                              @mastal I did try to change into .txt but sadly its not responding...not getting open...so I will try ur link...thanks...
                              Can you try to explain a bit more in detail? What did you do and what did not respond?

                              Comment

                              Latest Articles

                              Collapse

                              • SEQadmin2
                                Beyond CRISPR/Cas9: Understand, Choose, and Use the Right Genome Editing Tool
                                by SEQadmin2



                                CRISPR/Cas9 sparked the gene editing revolution for both research and therapeutics.1 But this system still showed severe issues that limited its applications. The most prominent were the heavy reliance on PAM sequences, delivery limitations, double-stranded breaks that prompt unintended edits and cell death, and editing inefficiency (both in targeting and in knock-in reliability).

                                Despite this, “CRISPR helped turn genome editing from a specialized technique into
                                ...
                                07-31-2026, 11:01 AM
                              • SEQadmin2
                                Proteomic Platforms: How to Choose the Right Analytical Strategy to Improve Detection and Clinical Applications
                                by SEQadmin2


                                Proteomics platforms are evolving rapidly, with advances in mass spectrometry and affinity-based approaches expanding what researchers can detect and at what scale. As the field moves toward deeper proteome coverage and clinical applications, scientists face an increasingly complex landscape of tools. This article will explore how researchers are navigating these choices to find the right platform for their work.

                                The systematic characterization of the human proteome has
                                ...
                                07-20-2026, 11:48 AM
                              • SEQadmin2
                                Advanced Sequencing Platforms Tackle Neuroscience’s Toughest Genomics Problems
                                by SEQadmin2



                                Genomics studies in neuroscience face a special challenge due to the brain’s complexity and scarcity of samples. Mapping changes in cell type and state using conventional next-generation sequencing methods remains challenging. Advances in technologies like single-cell sequencing, spatial transcriptomics, and long-read sequencing have opened the door to deeper studies of the brain and diseases like Alzheimer’s, amyotrophic lateral sclerosis (ALS), and schizophrenia.
                                ...
                                07-09-2026, 11:10 AM

                              ad_right_rmr

                              Collapse

                              News

                              Collapse

                              Topics Statistics Last Post
                              Started by SEQadmin2, 08-03-2026, 10:13 AM
                              0 responses
                              15 views
                              0 reactions
                              Last Post SEQadmin2  
                              Started by SEQadmin2, 07-31-2026, 02:55 AM
                              0 responses
                              32 views
                              0 reactions
                              Last Post SEQadmin2  
                              Started by SEQadmin2, 07-24-2026, 12:17 PM
                              0 responses
                              23 views
                              0 reactions
                              Last Post SEQadmin2  
                              Started by SEQadmin2, 07-23-2026, 11:41 AM
                              0 responses
                              21 views
                              0 reactions
                              Last Post SEQadmin2  
                              Working...