[BioC] Filtering BAM files by start position for VariantTools

Taylor, Sean D sdtaylor at fhcrc.org
Fri Aug 2 16:08:33 CEST 2013


Martin, it always makes me feel better when I see you scratching your head too! ;)

Sean

Sent from my iPod

On Aug 1, 2013, at 6:02 PM, "Martin Morgan" <mtmorgan at fhcrc.org> wrote:

> On 07/16/2013 05:40 PM, Michael Lawrence wrote:
>> The necessary update to VariantTools will propagate soon to devel. Or you
>> can grab it from svn.
> 
> This isn't building in devel; does it require something special with gmapR? Dan and I looked at this (??) for the conference, but were not quite able to master the automake foo required to get off the ground.
> 
> Martin
> 
>> 
>> Michael
>> 
>> 
>> On Tue, Jul 16, 2013 at 3:27 PM, Taylor, Sean D <sdtaylor at fhcrc.org> wrote:
>> 
>>>  In order to work through some of the code, I installed the devel version
>>> of R and updated all the packages. Now when I run tallyVariants() I get the
>>> following error message:****
>>> 
>>> ** **
>>> 
>>> Error in get(name, envir = asNamespace(pkg), inherits = FALSE) : ****
>>> 
>>>   object 'castList' not found****
>>> 
>>> ** **
>>> 
>>>> traceback()****
>>> 
>>> 12: get(name, envir = asNamespace(pkg), inherits = FALSE)****
>>> 
>>> 11: IRanges:::castList****
>>> 
>>> 10: safe_mclapply(ind, function(i, ...) {****
>>> 
>>>         FUN(gr[i], ...)****
>>> 
>>>     }, ...)****
>>> 
>>> 9: applyByChromosome(si, bam_tally_region, mc.cores = mc.cores)****
>>> 
>>> 8: .local(x, ...)****
>>> 
>>> 7: tallyVariants(x, tally.param)****
>>> 
>>> 6: tallyVariants(x, tally.param)****
>>> 
>>> 5: .local(x, ...)****
>>> 
>>> 4: callVariants(BamFile(x), ...)****
>>> 
>>> 3: callVariants(BamFile(x), ...)****
>>> 
>>> 2: callVariants(destination, tally.param)****
>>> 
>>> 1: callVariants(destination, tally.param)****
>>> 
>>> ** **
>>> 
>>> Perhaps this is something missing/changed in the devel version of IRanges?
>>> ****
>>> 
>>> ** **
>>> 
>>> Updated sessionInfo() below:****
>>> 
>>> ** **
>>> 
>>> R version 3.0.1 (2013-05-16)****
>>> 
>>> Platform: x86_64-unknown-linux-gnu (64-bit)****
>>> 
>>> ** **
>>> 
>>> locale:****
>>> 
>>> [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              ****
>>> 
>>>  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    ****
>>> 
>>>  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   ****
>>> 
>>>  [7] LC_PAPER=C                 LC_NAME=C                 ****
>>> 
>>>  [9] LC_ADDRESS=C               LC_TELEPHONE=C            ****
>>> 
>>> [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       ****
>>> 
>>> ** **
>>> 
>>> attached base packages:****
>>> 
>>> [1] grid      parallel  stats     graphics  grDevices utils     datasets *
>>> ***
>>> 
>>> [8] methods   base     ****
>>> 
>>> ** **
>>> 
>>> other attached packages:****
>>> 
>>> [1] BiocInstaller_1.11.3     latticeExtra_0.6-24
>>> lattice_0.20-15         ****
>>> 
>>>  [4] RColorBrewer_1.0-5       genoPlotR_0.8
>>> ade4_1.5-2              ****
>>> 
>>>  [7] gmapR_1.3.2              VariantTools_1.3.2
>>> VariantAnnotation_1.7.34****
>>> 
>>> [10] Rsamtools_1.13.24        Biostrings_2.29.13
>>> GenomicRanges_1.13.33   ****
>>> 
>>> [13] XVector_0.1.0            IRanges_1.19.18
>>> BiocGenerics_0.7.3      ****
>>> 
>>> ** **
>>> 
>>> loaded via a namespace (and not attached):****
>>> 
>>> [1] AnnotationDbi_1.23.16   Biobase_2.20.0          biomaRt_2.17.2
>>> ****
>>> 
>>>  [4] bitops_1.0-5            BSgenome_1.28.0         DBI_0.2-7
>>>      ****
>>> 
>>>  [7] GenomicFeatures_1.13.19 graph_1.39.3
>>> Matrix_1.0-12          ****
>>> 
>>> [10] RBGL_1.37.2             RCurl_1.95-4.1
>>> RSQLite_0.11.4         ****
>>> 
>>> [13] rtracklayer_1.20.2      stats4_3.0.1
>>> tools_3.0.1            ****
>>> 
>>> [16] XML_3.96-1.1            zlibbioc_1.6.0         ****
>>> 
>>>> ** **
>>> 
>>> ** **
>>> 
>>> Thanks again,****
>>> 
>>> Sean****
>>> 
>>> ** **
>>> 
>>> *From:* Michael Lawrence [mailto:lawrence.michael at gene.com]
>>> *Sent:* Saturday, July 13, 2013 1:59 PM
>>> *To:* Taylor, Sean D
>>> *Cc:* Michael Lawrence; Pages, Herve; Obenchain, Valerie J;
>>> bioconductor at r-project.org
>>> 
>>> *Subject:* Re: [BioC] Filtering BAM files by start position for
>>> VariantTools****
>>> 
>>>  ** **
>>> 
>>> ** **
>>> 
>>> ** **
>>> 
>>> On Sat, Jul 13, 2013 at 1:50 PM, Taylor, Sean D <sdtaylor at fhcrc.org>
>>> wrote:****
>>> 
>>> Thanks Michael, ****
>>> 
>>> This is an interesting idea. Usually, we resolve PCR/optical duplicates
>>> with the Picard MarkDuplicates command, which just chooses the read with
>>> the highest average quality. This approximates what you want, I think. ***
>>> *
>>> 
>>> Is the Picard MarkDuplicates command run by default? Or is this a separate
>>> command from a different package?****
>>> 
>>> ** **
>>> 
>>> It's a separate package, basically the Java implementation of samtools;
>>> you might that first and see how it improves your error rates, before
>>> taking a more complicated approach.****
>>> 
>>>     Also, I find it hard to believe that sequence errors would be causing
>>> you trouble at 10%, as long as you're filtering for quality and have decent
>>> coverage. PCR might in limited cases, and Picard effectively takes care of
>>> that.****
>>> 
>>> 10% is fine, but we have problems at 1% and lower. I think even the
>>> defaults in tallyVariants() use 1% as a cutoff if I’m not mistaken.****
>>> 
>>>  ****
>>> 
>>>  ** **
>>> 
>>> It uses a ~4% cutoff. And yes, you'll start running into issues around 1%.
>>> Calling at such a low frequency is kind of ambitious.****
>>> 
>>>  ****
>>> 
>>>     What you want is to specify the cycleBreaks argument to
>>> VariantTallyParam. It allows you to define bins by cycle. So if you made
>>> bins for all 100bp, you could do things like generate a consensus by read
>>> family. A family corresponding to position X would be cycle bin #1 at X,
>>> cycle bin #2 at X+1, etc. Then just pick the alt (or ref) with the highest
>>> count. Might be tricky to implement efficiently for the whole genome. Of
>>> course, this assumes you've got single end reads, otherwise this won't
>>> work, because the mate is not considered.****
>>> 
>>> Cool, I will try that out, that may be just what I was looking for. It
>>> might be tricky for the whole genome, but we are restricting ourselves to
>>> just the mitochondrial genome. Still gives us several thousand start sites
>>> to work from but should be easier than the whole genome. As for single end
>>> reads, can I just filter on the strand (i.e. ‘+’ or ‘-‘)? Or will I have to
>>> perform separate alignments for each of the paired reads?****
>>> 
>>>  ****
>>> 
>>>  ** **
>>> 
>>> Now that I think about it, you should be fine just considering the
>>> alignments individually (as if they were unpaired).****
>>> 
>>>  ****
>>> 
>>> ** **
>> 
>>    [[alternative HTML version deleted]]
>> 
>> 
>> 
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