I am running the following command:
bwa mem -t 4 /users/person/resources/reference/hg19/genome/ucsc.hg19.fasta 160095-T_S2_L003_R1_001.fastq.gz 160095-t_s2_l003_r2_001.fastq.gz > 160095-T_S2_L003_R1_001.fastq.gz.bwa.sam
With the following bwa messages where all four orientations are being skipped:-
[M::bwa_idx_load_from_disk] read 0 ALT contigs
[M::process] read 546760 sequences (40000002 bp)...
[M::process] read 546534 sequences (40000140 bp)...
[M::mem_pestat] # candidate unique pairs for (FF, FR, RF, RR): (1, 1, 0, 0)
[M::mem_pestat] skip orientation FF as there are not enough pairs
[M::mem_pestat] skip orientation FR as there are not enough pairs
[M::mem_pestat] skip orientation RF as there are not enough pairs
[M::mem_pestat] skip orientation RR as there are not enough pairs
[mem_sam_pe] paired reads have different names: "NS500784:187:HHYNGAFXX:4:11401:17815:1049", "NS500784:187:HHYNGAFXX:1:11101:13503:1043"
[mem_sam_pe] paired reads have different names: "NS500784:187:HHYNGAFXX:4:11401:8106:1064", "NS500784:187:HHYNGAFXX:1:11101:4077:1043"
When I open the sam file it looks like this:
@SQ SN:chrM LN:16571
@SQ SN:chr1 LN:249250621
@SQ SN:chr2 LN:243199373
@SQ SN:chr3 LN:198022430
@SQ SN:chr4 LN:191154276
@SQ SN:chr5 LN:180915260
@SQ SN:chr6 LN:171115067
@SQ SN:chr7 LN:159138663
@SQ SN:chr8 LN:146364022
@SQ SN:chr9 LN:141213431
@SQ SN:chr10 LN:135534747
@SQ SN:chr11 LN:135006516
@SQ SN:chr12 LN:133851895
@SQ SN:chr13 LN:115169878
@SQ SN:chr14 LN:107349540
@SQ SN:chr15 LN:102531392
@SQ SN:chr16 LN:90354753
@SQ SN:chr17 LN:81195210
@SQ SN:chr18 LN:78077248
@SQ SN:chr19 LN:59128983
@SQ SN:chr20 LN:63025520
@SQ SN:chr21 LN:48129895
@SQ SN:chr22 LN:51304566
@SQ SN:chrX LN:155270560
@SQ SN:chrY LN:59373566
@SQ SN:chr1_gl000191_random LN:106433
@SQ SN:chr1_gl000192_random LN:547496
@SQ SN:chr4_ctg9_hap1 LN:590426
@SQ SN:chr4_gl000193_random LN:189789
@SQ SN:chr4_gl000194_random LN:191469
@SQ SN:chr6_apd_hap1 LN:4622290
@SQ SN:chr6_cox_hap2 LN:4795371
@SQ SN:chr6_dbb_hap3 LN:4610396
@SQ SN:chr6_mann_hap4 LN:4683263
@SQ SN:chr6_mcf_hap5 LN:4833398
@SQ SN:chr6_qbl_hap6 LN:4611984
@SQ SN:chr6_ssto_hap7 LN:4928567
@SQ SN:chr7_gl000195_random LN:182896
@SQ SN:chr8_gl000196_random LN:38914
@SQ SN:chr8_gl000197_random LN:37175
@SQ SN:chr9_gl000198_random LN:90085
@SQ SN:chr9_gl000199_random LN:169874
@SQ SN:chr9_gl000200_random LN:187035
@SQ SN:chr9_gl000201_random LN:36148
@SQ SN:chr11_gl000202_random LN:40103
@SQ SN:chr17_ctg5_hap1 LN:1680828
@SQ SN:chr17_gl000203_random LN:37498
@SQ SN:chr17_gl000204_random LN:81310
@SQ SN:chr17_gl000205_random LN:174588
@SQ SN:chr17_gl000206_random LN:41001
@SQ SN:chr18_gl000207_random LN:4262
@SQ SN:chr19_gl000208_random LN:92689
@SQ SN:chr19_gl000209_random LN:159169
@SQ SN:chr21_gl000210_random LN:27682
@SQ SN:chrUn_gl000211 LN:166566
@SQ SN:chrUn_gl000212 LN:186858
@SQ SN:chrUn_gl000213 LN:164239
@SQ SN:chrUn_gl000214 LN:137718
@SQ SN:chrUn_gl000215 LN:172545
@SQ SN:chrUn_gl000216 LN:172294
@SQ SN:chrUn_gl000217 LN:172149
@SQ SN:chrUn_gl000218 LN:161147
@SQ SN:chrUn_gl000219 LN:179198
@SQ SN:chrUn_gl000220 LN:161802
@SQ SN:chrUn_gl000221 LN:155397
@SQ SN:chrUn_gl000222 LN:186861
@SQ SN:chrUn_gl000223 LN:180455
@SQ SN:chrUn_gl000224 LN:179693
@SQ SN:chrUn_gl000225 LN:211173
@SQ SN:chrUn_gl000226 LN:15008
@SQ SN:chrUn_gl000227 LN:128374
@SQ SN:chrUn_gl000228 LN:129120
@SQ SN:chrUn_gl000229 LN:19913
@SQ SN:chrUn_gl000230 LN:43691
@SQ SN:chrUn_gl000231 LN:27386
@SQ SN:chrUn_gl000232 LN:40652
@SQ SN:chrUn_gl000233 LN:45941
@SQ SN:chrUn_gl000234 LN:40531
@SQ SN:chrUn_gl000235 LN:34474
@SQ SN:chrUn_gl000236 LN:41934
@SQ SN:chrUn_gl000237 LN:45867
@SQ SN:chrUn_gl000238 LN:39939
@SQ SN:chrUn_gl000239 LN:33824
@SQ SN:chrUn_gl000240 LN:41933
@SQ SN:chrUn_gl000241 LN:42152
@SQ SN:chrUn_gl000242 LN:43523
@SQ SN:chrUn_gl000243 LN:43341
@SQ SN:chrUn_gl000244 LN:39929
@SQ SN:chrUn_gl000245 LN:36651
@SQ SN:chrUn_gl000246 LN:38154
@SQ SN:chrUn_gl000247 LN:36422
@SQ SN:chrUn_gl000248 LN:39786
@SQ SN:chrUn_gl000249 LN:38502
@PG ID:bwa PN:bwa VN:0.7.15-r1140 CL:bwa/users/person/resources/reference/hg19/genome/ucsc.hg19.fasta 160095-T_S2_L004_R1_001.fastq.gz 160095-t_s2_l003_r2_001.fastq.gz
BUT when I use samtools to convert it to a bam file it's empty!
Can anyone advise?
It's not a problem with bwa but it's a problem with your pair of fastq. You're mapping two fastqs that come from different lanes (L004 and L003)
160095-T_S2_L004_R1_001.fastq.gz should be mapped with 160095-T_S2_L004_R2_001.fastq.gz (R1 and R2)
160095-t_s2_l003_r1_001.fastq.gz should be mapped with 160095-t_s2_l003_r2_001.fastq.gz (R1 and R2)
Hey, yeah, that was a typo - nothing was working so I tried different combinations of lanes just incase.
The above is from read1 and read2 from Lane 3.
I also tried:
read1 lane3 with read2 lane4
and I also concatenated R1 from both lane 3 and lane 4, and then tried to align with R2 from lane 3 and 4 with the same problem.
Thank you for noticing I didn't properly go through my question! I have tried all possible combinations of read1 and 2 from lane 3 and 4 from this sample because it is not aligning. and all have the same outcome - skipped all 4 orientations. I have 28 samples that aligned well, but not the case for this one...
do you have any other suggestions as to why this would be? is it the case that it has just come from different samples? do you think there was a sequencing error? library? labelling? pair names? and are you able to advise on what to do next - how to fix this problem?
thanks
there is something wrong with your fastqs. You should have the same read name in the R1 and R2 fastqs.
check for the same read names:
paste <(gunzip -c file.R1.fastq.gz | paste - - - - | cut -f 1) paste <(gunzip -c file.R2.fastq.gz | paste - - - - | cut -f 1) | grep -m 1 -F "NS500784:187:HHYNGAFXX:4:11401:17815:1049"
you should get two columns with the same read name R1/R2.
How to fix this ? I wouldn't trust this kind of data anyway. There is something wrong in your data.
When you notice data not aligning as expected the first thing you should check is to take a few reads and blast them at NCBI to make sure you are looking at the right genome/sample. It won't be the first time a sample has been contaminated (somewhere along the line) and the data is not correct to begin with.
Have you scanned and trimmed your data for presence of adapters?
If all that checks out then try repair.sh tool from BBMap suite that can fix read order issues in PE data files. You would use it like repair.sh in1=r1.fq.gz in2=r2.fq.gz out1=fixed1.fq.gz out2=fixed2.fq.gz outsingle=singletons.fq.gz
It appears that the names of the file do not match the data. From your example:
"NS500784:187:HHYNGAFXX:4:11401:17815:1049", "NS500784:187:HHYNGAFXX:1:11101:13503:1043"
The first read is from lane 4 (the number after the flow cell identifier HHYNGAFXX), while the second is from lane 1.
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My guess is that your paired files are not properly paired. The names of your reads don't seem to match between your pairs.
I get this error from read1 and 2 from lane 3 and 4 of this sample. all my other samples were fine. so I also thought something similar - so I tried all alignment combinations of read1 and 2 from the different lanes with the same problem - I also tried concatenation read1s from lane 3 and 4 and aligned this with read2s from lane 3 and 4.
is there a way to fix the different names of the reads?
How to fix it? Find the right pairs.
What does fastqc / multiqc look like? Any major flags? Is it possible that your forward / reverse reads are randomly sorted?
fastqc was fine - no flags. this is a problem with read 1 and read 2 from lane 3 and 4 of this sample. I have 29, and this is the only one with this problem