Entering edit mode
Hi,
I am analyzing a matched pair tumor/normal rna-seq data set. After
aligning with bowtie2 against UCSC hg19 index, I am trying to get the
counts for each of the samples using the iGenomes UCSC GTF file. I
came across the following tutorial which shows different ways to do it
in Bioconductor:
http://faculty.ucr.edu/~tgirke/HTML_Presentations/Manuals/Workshop_Dec
_12_16_2013/Rrnaseq/Rrnaseq.pdf
Following along slide 28 "Read Counting with countOverlaps", I am able
to generate the counts but get the following Warnings. I just want to
be sure that there is nothing to be worried about because I don't
understand the meaning of these warnings. My code is as follows:
> library(GenomicFeatures)
Loading required package: AnnotationDbi
> library(Rsamtools)
> library(rtracklayer)
> txdb <- loadDb("./data/ucsc_igenomes_hg19_gtf.sqlite")
> eByg <- exonsBy(txdb, by="gene")
> head(eByg)
GRangesList of length 6:
$A1BG
GRanges with 8 ranges and 2 metadata columns:
seqnames ranges strand | exon_id exon_name
<rle> <iranges> <rle> | <integer> <character>
[1] chr19 [58858172, 58858395] - | 163177 <na>
[2] chr19 [58858719, 58859006] - | 163178 <na>
[3] chr19 [58861736, 58862017] - | 163179 <na>
[4] chr19 [58862757, 58863053] - | 163180 <na>
[5] chr19 [58863649, 58863921] - | 163181 <na>
[6] chr19 [58864294, 58864563] - | 163182 <na>
[7] chr19 [58864658, 58864693] - | 163183 <na>
[8] chr19 [58864770, 58864865] - | 163184 <na>
$A1BG-AS1
GRanges with 4 ranges and 2 metadata columns:
seqnames ranges strand | exon_id exon_name
[1] chr19 [58863336, 58864410] + | 156640 <na>
[2] chr19 [58864745, 58864840] + | 156641 <na>
[3] chr19 [58865080, 58865223] + | 156642 <na>
[4] chr19 [58865735, 58866549] + | 156643 <na>
...
<4 more elements>
---
seqlengths:
chr12 chr8 ... chr1_gl000192_random
NA NA ... NA
> samples = c("BRPC13-1118_L1.D710_501.sorted",
"BRPC_13-764_L2.sorted", "DU04_PBMC_RNA_L1.sorted",
"DU06_PBMC_RNA_L1.sorted")
>
> samples
[1] "BRPC13-1118_L1.D710_501.sorted" "BRPC_13-764_L2.sorted"
[3] "DU04_PBMC_RNA_L1.sorted" "DU06_PBMC_RNA_L1.sorted"
>
> samplespath <- paste("./", samples, ".bam", sep="")
>
> samplespath
[1] "./BRPC13-1118_L1.D710_501.sorted.bam"
[2] "./BRPC_13-764_L2.sorted.bam"
[3] "./DU04_PBMC_RNA_L1.sorted.bam"
[4] "./DU06_PBMC_RNA_L1.sorted.bam"
>
> names(samplespath) <- samples
>
> samplespath
BRPC13-1118_L1.D710_501.sorted
BRPC_13-764_L2.sorted
"./BRPC13-1118_L1.D710_501.sorted.bam"
"./BRPC_13-764_L2.sorted.bam"
DU04_PBMC_RNA_L1.sorted
DU06_PBMC_RNA_L1.sorted
"./DU04_PBMC_RNA_L1.sorted.bam"
"./DU06_PBMC_RNA_L1.sorted.bam"
>
> countDF <- data.frame(row.names=names(eByg))
>
> countDF
data frame with 0 columns and 23710 rows
>
> dim(countDF)
[1] 23710 0
>
> for(i in samplespath) {
+ aligns <- readGAlignmentsFromBam(i)
+ counts <- countOverlaps(eByg, aligns, ignore.strand=TRUE)
+ countDF <- cbind(countDF, counts)
+ }
Warning messages:
1: In .Seqinfo.mergexy(x, y) :
Each of the 2 combined objects has sequence levels not in the other:
- in 'x': chr6_cox_hap2, chr6_dbb_hap3, chr6_ssto_hap7,
chr6_qbl_hap6, chr6_mann_hap4, chr6_mcf_hap5, chr6_apd_hap1,
chrUn_gl000228, chr17_ctg5_hap1, chr19_gl000209_random,
chr4_ctg9_hap1, chrUn_gl000222, chrUn_gl000223, chr1_gl000191_random,
chr7_gl000195_random, chrUn_gl000213, chrUn_gl000220,
chr17_gl000205_random, chrUn_gl000212, chrUn_gl000218, chrUn_gl000219,
chrUn_gl000211, chr4_gl000193_random, chr4_gl000194_random,
chr1_gl000192_random
- in 'y': chrM
Make sure to always combine/compare objects based on the same
reference
genome (use suppressWarnings() to suppress this warning).
2: In .Seqinfo.mergexy(x, y) :
Each of the 2 combined objects has sequence levels not in the other:
- in 'x': chr6_cox_hap2, chr6_dbb_hap3, chr6_ssto_hap7,
chr6_qbl_hap6, chr6_mann_hap4, chr6_mcf_hap5, chr6_apd_hap1,
chrUn_gl000228, chr17_ctg5_hap1, chr19_gl000209_random,
chr4_ctg9_hap1, chrUn_gl000222, chrUn_gl000223, chr1_gl000191_random,
chr7_gl000195_random, chrUn_gl000213, chrUn_gl000220,
chr17_gl000205_random, chrUn_gl000212, chrUn_gl000218, chrUn_gl000219,
chrUn_gl000211, chr4_gl000193_random, chr4_gl000194_random,
chr1_gl000192_random
- in 'y': chrM
Make sure to always combine/compare objects based on the same
reference
genome (use suppressWarnings() to suppress this warning).
3: In .Seqinfo.mergexy(x, y) :
Each of the 2 combined objects has sequence levels not in the other:
- in 'x': chr6_cox_hap2, chr6_dbb_hap3, chr6_ssto_hap7,
chr6_qbl_hap6, chr6_mann_hap4, chr6_mcf_hap5, chr6_apd_hap1,
chrUn_gl000228, chr17_ctg5_hap1, chr19_gl000209_random,
chr4_ctg9_hap1, chrUn_gl000222, chrUn_gl000223, chr1_gl000191_random,
chr7_gl000195_random, chrUn_gl000213, chrUn_gl000220,
chr17_gl000205_random, chrUn_gl000212, chrUn_gl000218, chrUn_gl000219,
chrUn_gl000211, chr4_gl000193_random, chr4_gl000194_random,
chr1_gl000192_random
- in 'y': chrM
Make sure to always combine/compare objects based on the same
reference
genome (use suppressWarnings() to suppress this warning).
4: In .Seqinfo.mergexy(x, y) :
Each of the 2 combined objects has sequence levels not in the other:
- in 'x': chr6_cox_hap2, chr6_dbb_hap3, chr6_ssto_hap7,
chr6_qbl_hap6, chr6_mann_hap4, chr6_mcf_hap5, chr6_apd_hap1,
chrUn_gl000228, chr17_ctg5_hap1, chr19_gl000209_random,
chr4_ctg9_hap1, chrUn_gl000222, chrUn_gl000223, chr1_gl000191_random,
chr7_gl000195_random, chrUn_gl000213, chrUn_gl000220,
chr17_gl000205_random, chrUn_gl000212, chrUn_gl000218, chrUn_gl000219,
chrUn_gl000211, chr4_gl000193_random, chr4_gl000194_random,
chr1_gl000192_random
- in 'y': chrM
Make sure to always combine/compare objects based on the same
reference
genome (use suppressWarnings() to suppress this warning).
>
I also wanted to verify if what I am doing is correct for paired end
reads.
Thanks,
- Pankaj
=======================================
sessionInfo()
R version 3.0.3 (2014-03-06)
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=en_US.UTF-8 LC_NAME=C
[9] LC_ADDRESS=C LC_TELEPHONE=C
[11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
attached base packages:
[1] stats graphics grDevices utils datasets methods base
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