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  • gibberwocky
    Junior Member
    • Mar 2013
    • 8

    #1

    SRA fastq-dump puzzle

    Hopefully someone can help me out here as I've been scratching my head now for a couple of days to try and solve the puzzle.

    I've downloaded the SRA file for SRR081275, and have tried various different options to generate $file_1.fastq and $file_2.fastq files for mapping. I'll present two examples here:

    1) ${SRATK}/fastq-dump --split-3 -O ${DATA}/$i ${DATA}/SRR081275.sra
    2) ${SRATK}/fastq-dump -I --split-3 -O ${DATA}/$i ${DATA}/SRR081275.sra

    And an example of a read from $file_1.fastq in each case:

    1)

    @SRR081275.1 HWI-EA332_307V4AAXX:3:1:1008:1695 length=36
    GTGGGTGTGCATTGTCCTTACCTGCTGGCAGACAAT
    +SRR081275.1 HWI-EA332_307V4AAXX:3:1:1008:1695 length=36
    IIIIIIIIIIIIIIII?II;D;A-55%5)&)#'(,9

    2)

    @SRR081275.1.1 HWI-EA332_307V4AAXX:3:1:1008:1695 length=36
    GTGGGTGTGCATTGTCCTTACCTGCTGGCAGACAAT
    +SRR081275.1.1 HWI-EA332_307V4AAXX:3:1:1008:1695 length=36
    IIIIIIIIIIIIIIII?II;D;A-55%5)&)#'(,9


    In each case the reads are mapped using BWA
    Code:
    bwa aln -t 4 -e 5 -d 5 -q 20 -f ${DATA}/$i/"$i"_1.sai ${REF} ${DATA}/$i/"$i"_1.fastq.gz 
    bwa aln -t 4 -e 5 -d 5 -q 20 -f ${DATA}/$i/"$i"_2.sai ${REF} ${DATA}/$i/"$i"_2.fastq.gz 
    bwa sampe -f ${DATA}/$i/$i.sam ${REF} \
      -r @RG"\t"ID:$i"\t"SM:$i"\t"LB:$i"\t"PL:Illumina \
      ${DATA}/$i/"$i"_1.sai ${DATA}/$i/"$i"_2.sai \
      ${DATA}/$i/"$i"_1.fastq.gz ${DATA}/$i/"$i"_2.fastq.gz
    converted to BAM
    Code:
    samtools view -bhT ${REF} ${DATA}/$i/$i.sam > ${DATA}/$i/$i.bam
    cleaned
    Code:
    java -d64 -Xmx4g -jar ${PICARD}/CleanSam.jar \
      INPUT=${DATA}/$i/$i.bam \
      OUTPUT=${DATA}/$i/$i.clean.bam \
      VALIDATION_STRINGENCY=SILENT
    mates fixed
    Code:
    java -d64 -Xmx4g -jar ${PICARD}/FixMateInformation.jar \
      INPUT=${DATA}/$i/$i.clean.bam \
      SORT_ORDER=coordinate \
      VALIDATION_STRINGENCY=SILENT
    duplicates marked
    Code:
    java -d64 -Xmx4g -jar ${PICARD}/MarkDuplicates.jar \
      INPUT=${DATA}/$i/$i.clean.bam \
      OUTPUT=${DATA}/$i/$i.md.bam \
      ASSUME_SORTED=true \
      METRICS_FILE=${DATA}/$i/$i.md.metrics \
      VALIDATION_STRINGENCY=SILENT
    and finally sent to GASV
    Code:
    cd ${GASV}
    perl ${GASV}/BAM_preprocessor.pl \
      ${DATA}/$i/$i.md.bam \
      -CHROMOSOME_NAMING ${CHRS} \
      -OUTPUT_PREFIX ${DATA}/$i/GASV/gasv
    .

    In example (1) Picard's MarkDuplicates returns 1371073/2000000 duplicate reads and 0 optical duplicates. Whilst in example (2) it returns 15523/2000000 duplicate reads and 0 optical duplicates.

    When sent to GASV, example (1) can have its insert sizes calculated from Lmin and Lmax, and causes no problems. Whilst for example (2) GASV fails to calculate the insert sizes and as a result fails to identify any discordant reads.

    It seems I'm failing to generate a BAM file that will work in both Picard's MarkDuplicates AND GASV, and it appears to be due to the read definition line. I've tried to address this by going through all of the fastq-dump options, and attempting to alter the default READ_NAME_REGEX in Picard's MarkDuplicates, but don't appear to be getting anywhere.

    Is anyone able to help?

  • gibberwocky
    Junior Member
    • Mar 2013
    • 8

    #2
    I forgot to mention that after running the fast-dump command I used a subset of the fastq file to make checking the different command options quicker
    Code:
    cat ${DATA}/$i/SRR081275_1.fastq | sed -n 1,4000000p > ${DATA}/$i/"$i"_1.fastq
    cat ${DATA}/$i/SRR081275_2.fastq | sed -n 1,4000000p > ${DATA}/$i/"$i"_2.fastq
    head ${DATA}/$i/"$i"_1.fastq
    head ${DATA}/$i/"$i"_2.fastq
    bgzip -f "$i"_1.fastq
    bgzip -f "$i"_2.fastq
    Also, I have NGS data from Illumain GAIIx 1.8 format which works fine in both Picard MarkDuplicates and GASV, the fastq read format for which looks like this:

    @HWUSI-EAS1643R:30:FC:1:1:3636:1000 1:N:0:CGATGT
    NTTCCTACTCCGACATGCTAAAGATCCATGAAACAGAGTGTTTGCCAACAAGTCCAGATTTTTACCAGGCTCATCTCTTCAGTTTCAAAGAATCAGTTTC
    +
    #***,/223/@:@@@@@@@@:<<<<@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@:@@@@@@22.2577577@@@@@@@@@@@228@@@@@@

    Comment

    • tmacme
      Junior Member
      • Oct 2011
      • 3

      #3
      Did you check the bam file header. What's the read name? I encounter a warning for READ_NAME_REGEX unalbe to detect "read name" during MarkDuplicate with picardtools. And the output shows 0 optical duplicate.

      Comment

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