Problem With Bam And/Or Bai Files

Question: Problem With Bam And/Or Bai Files

7.1 years ago by

Mike Dufault • 270 wrote:

Hello Galaxy Team, I have been using Galaxy for SNP detection for with great success. Basically, I followed the screen-cast from Anton without any problems. The only change was to use the BWA instead of Bowtie. Until now, I have always assigned my raw read files to the hg19 format. Now I want to try the GATK pipeline to analyze my samples but I am running into a problem with the bam/bai files. Here is what I did. I imported my Illumina paired end reads into Galaxy and assigned them to the hg_g1k_v37 format instead of the Hg19 format. From there, I again followed the exact same process: FastQ Groomer, Summary Statistics, Boxplots, Align with BWA, filter on SAM, SAM-to-Bam, generate bai file. I made sure that hg_g1k_37 was chosen for the format for all of these steps that required that information. Everything seemed to run successfully as all of the boxed turned green. When I tried to view the bam file in IGV (as a QC step before the GATK pipeline), I received the following error: "Error reading bam file. This usually indicates a problem with the index (bai) file. ArrayIndexOutofBoundsException: 4682 (4682)." I did the exact same analysis using the Hg19 format and my bam/bai files worked perfectly fine in the IGV viewer. Can anyone tell me what the problem is and how to fix it? Thanks, Mike Dufault

bwa alignment bowtie • 2.2k views

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modified 7.1 years ago by Jennifer Hillman Jackson ♦ 25k • written 7.1 years ago by Mike Dufault • 270

7.1 years ago by

Jim Robinson • 150

Jim Robinson • 150 wrote:

Hi Mike, Someone from the Galaxy team can perhaps give some insight on what went wrong, I can comment on the error message from IGV. That error is thrown from Picard, in every case I've investigated so far it was traced to a problem with the index. The most common causes are (1) a problem with the sequence dictionary in the BAM header itself, specifically incorrect sequence lengths, and (2) indexing an un-sorted BAM. Apparently samtools will make invalid indexes from such files without any complaints in both cases. You can even use samtools tview on such files, it happily will show you some random region when you query. I don't see a "Sort" step in your workflow, maybe that's the problem? Please CC me on any reply, I might miss it in the list. Jim

ADD COMMENT • link written 7.1 years ago by Jim Robinson • 150

Sending to galaxy-dev ... On Thu, Oct 27, 2011 at 5:51 AM, Jim Robinson Useful background re: "Error reading bam file. This usually indicates a problem with the index (bai) file. ArrayIndexOutofBoundsException: 4682 (4682)." Any idea what tools produce that kind of thing? That is news to me - I recall "samtools index" being recommended as a way to determine if a BAM files was sorted or not (error on unsorted, you get an index if it was sorted) and again from memory this is what Galaxy uses internally as part of preparing BAM files on upload. Might this be tied to a specific version of samtools? e.g. a possible regression? Thanks, Peter

ADD REPLY • link written 7.1 years ago by Peter Cock • 1.4k

Its possible the sorting problem was a specific version and now gives an error. The incorrect index caused by bad sequence lengths is a recurrent problem, but I do not know what tool produces such headers. Perhaps someone who has experienced this can chime in. I'm not a samtools expert just sharing my experience on what has caused this error int the past. It does seem that, as a general rule, that these index problems result in errors from Picard (which the GATK uses), while samtools can fail silently and sometimes and give you an unrelated query region. Jim

ADD REPLY • link written 7.1 years ago by Jim Robinson • 150

Hi all, I appreciate all of the discussion related to this issue. I still don't understand why I should only see this issue when I choose the hg_g1k_v37 format but not when I choose the Hg_19 format? I realize that I would need to ensure that the Bam files are sorted correctly before I enter the GATK pipline, but all of this is before that process. When my read files are processed through to .bam files using the hg_19 format, I can view them in IGV without a problem. It is only when I use the hg_g1k_v37 format that I receive an error from IGV. It seems to me that the process that I am using in Galaxy should be identical except for the reference genome format (i.e. hg_19 or hg_g1k_v37). I am at a loss of how to proceed. Does anyone have ideas? Thanks, Mike Subject: Re: [galaxy-user] Problem with bam and/or bai files To: "Peter Cock" <p.j.a.cock@googlemail.com> Cc: "Galaxy Dev" <galaxy-dev@bx.psu.edu>, "Mike Dufault" <dufaultm@yahoo.com>, "galaxy-user" <galaxy-user@lists.bx.psu.edu> Date: Thursday, October 27, 2011, 9:58 AM Its possible the sorting problem was a specific version and now gives an error. The incorrect index caused by bad sequence lengths is a recurrent problem, but I do not know what tool produces such headers. Perhaps someone who has experienced this can chime in. I'm not a samtools expert just sharing my experience on what has caused this error int the past. It does seem that, as a general rule, that these index problems result in errors from Picard (which the GATK uses), while samtools can fail silently and sometimes and give you an unrelated query region. Jim

ADD REPLY • link written 7.1 years ago by Mike Dufault • 270

7.1 years ago by

Jennifer Hillman Jackson ♦ 25k

United States

Jennifer Hillman Jackson ♦ 25k wrote:

Hi Mike, Are you using the Galaxy Main instance at http://usegalaxy.org? If not, can you duplicate when using Main? If on Main, and you want to share a history link with me, I can take a look. Use "Options -> Share or Publish", generate link (or add me as a share user), and email that back to me directly. Hopefully we can help, Jen Galaxy team -- Jennifer Jackson http://usegalaxy.org http://galaxyproject.org/wiki/Support

ADD COMMENT • link written 7.1 years ago by Jennifer Hillman Jackson ♦ 25k

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