.mem and sam files generated as empty

[kirasato0211]

Hi,
I am using ASGAL tool to find MET14 deletion and EGFR variation events in the samples. I am running genome wide analysis for these two genes. ASGAL run is successful but I am getting .mem and sam file as empty and hence no events reported in the final files.

command I used is as below:

./asgal --multi -g genome.fa -a annotation2.gtf -s sample1.fastq.gz -s2 sample2.fastq.gz -t transcript.fa --allevents -o output

could you please help me in this case as soon as possible?

[ldenti]

Hi, can you please send the tree view of the output folder (command tree is good enough)? Moreover, where did you get the gtf from? Can you share it?

[kirasato0211]

Hi,
Below is a tree view of output folder.

.
|-- ASGAL
|   |-- ENSG00000105976.events.csv
|   |-- ENSG00000105976.mem
|   |-- ENSG00000105976.sam
|   |-- ENSG00000146648.events.csv
|   |-- ENSG00000146648.mem
|   `-- ENSG00000146648.sam
|-- ASGAL.csv
|-- annos
|   |-- ENSG00000105976.gtf
|   |-- ENSG00000105976.gtf.db
|   |-- ENSG00000105976.gtf.sg
|   |-- ENSG00000146648.gtf
|   |-- ENSG00000146648.gtf.db
|   `-- ENSG00000146648.gtf.sg
|-- logs
|   |-- ASGAL
|   |   |-- ENSG00000105976
|   |   `-- ENSG00000146648
|   |-- salmon_index.log
|   |-- salmon_quant.log
|   `-- samtools.log
|-- refs
|   `-- chr7.fa
|-- salmon
|   |-- salmon.bam
|   |-- salmon.bam.bai
|   |-- salmon_index
|   |   |-- duplicate_clusters.tsv
|   |   |-- hash.bin
|   |   |-- header.json
|   |   |-- indexing.log
|   |   |-- quasi_index.log
|   |   |-- refInfo.json
|   |   |-- rsd.bin
|   |   |-- sa.bin
|   |   |-- txpInfo.bin
|   |   `-- versionInfo.json
|   `-- salmon_out
|       |-- aux_info
|       |   |-- ambig_info.tsv
|       |   |-- expected_bias.gz
|       |   |-- fld.gz
|       |   |-- meta_info.json
|       |   |-- observed_bias.gz
|       |   |-- observed_bias_3p.gz
|       |   `-- unmapped_names.txt
|       |-- cmd_info.json
|       |-- libParams
|       |   `-- flenDist.txt
|       |-- lib_format_counts.json
|       |-- logs
|       |   `-- salmon_quant.log
|       `-- quant.sf
`-- samples
    |-- ENSG00000105976.fa
    `-- ENSG00000146648.fa

12 directories, 45 files

I have fetched the annotations for MET and EGFR from gencode annotations and give it as input for ASGAL command.

[ldenti]

Can you check if the .fa files in the samples directory and the .gtf files in the annos directory are empty or not? Moreover, can you share the salmon.bam file?

[kirasato0211]

I can see the .fa files in the samples directory are non-empty but one of the file in the annos directory is empty and other one is non-empty. Please find attached here zip file which contains input annotations file(annotation2.gtf), the .gtf files from annos directory and the salmon.bam file.
Attachment.zip

[ldenti]

In annotation2.gtf both the transcripts of each gene share the same transcript_id. This produces unpredictable behaviours (gffutils library combines the two trancripts in a single transcript).

I manually edited the annotations (you can find it here) and now asgal output is non empty.

Let me know if this new annotation fixed your problem.

[kirasato0211]

Thank you for pointing it out. It helped me to run ASGAL successfully. However, there is no event reported in the output. I am expecting MET exon 14 skipping event to be reported in the output. I am sure that the samples i am using have MET14 deletion event and the EGFR variation.

Please have a look at the modified annotation file i am using.
annotation.zip
If i am interested in MET exon 14 skipping event to be reported in the output, do i need to mention exon 14 annotations in gtf file?

Could you please help me to understand how ASGAL report events?

[ldenti]

mmm that's strange (when I used the salmon.bam you shared with me, I found 2 events). So there must be some other issue.

Are the .sam files empty?

(if you haven't done it yet) I suggest removing the .gtf.db files in the annos folder since they may refer to the old (incomplete) annotations and rerun (or you can just change output folder).

ASGAL reports a csv describing the events: one line per event with type of event (e.g. ES for exon skipping), genomic coordinates, and other information (the example you can find here describes better the output format).

[kirasato0211]

could you please let me know how you found 2 events using salmon.bam file? SAM files are not empty. I tried removing .gtf.db files in the annos folder and also tried to change output folder. Unfortunately, it didnt help me. Still there are no events reported in the output file.

[ldenti]

I created the two samples using

samtools fastq -1 sample_1.fq -2 sample_2.fq salmon.bam

and then I ran asgal (as you did) on the edited annotation I sent you.

I checked the annotation you sent me and it contains only 1 transcript per gene (I'm using the initial one with 2 transcripts per gene). I think this is the reason why you are not getting any event.

[kirasato0211]

I run ASGAL with the edited annotation file you have sent to me and it didnt work. Then i used the salmon.bam file to generate the samples as you mentioned in above command and then run ASGAL. Unfortunately, it didnt help me.

Please send me the commands you have used to get the output.

[ldenti]

I used these files (annotation, transcripts, and samples). The reference I used is chr7 only, downloaded from ensembl (link). Edit: you have to change the header of the fasta entry from >7 to >chr7 otherwise asgal crashes.

I then ran:

asgal --multi -g Homo_sapiens.GRCh38.dna.chromosome.7.fa -a annotation2.edit.gtf -s sample_1.fq -s2 sample_2.fq -t transcripts2.fa --allevents -o output

and I obtained these events:

Type,Start,End,Support,Transcripts,file
ES,55019366,55155829,16,ENST00000275493.7,output/ASGAL/ENSG00000146648.events.csv
ES,116771655,116774880,24,ENST00000318493.11,output/ASGAL/ENSG00000105976.events.csv

Let me know if these files work for you

[kirasato0211]

Thank You. These files worked for me. The genome file i was using earlier has chr7 in the header. However it has repeat masked bases and 50 bases per line. May be that was causing issue.

Thank you for helping in this case. I have tested it on positive samples and will soon test it on negative samples too.

[gdv]

Hi, please notice that the official asgal release (not the one on the agilent hub) is now at version 1.1.2.
May you please try that version? It should suffice to run

sudo docker run -v "$PWD"/asgalgw_data:/data registry-dev.scs.agilent.com/algolab/galig:v1.1.1

Best

[kirasato0211]

could you please let me know from where i can get the latest asgal release (version 1.1.2)?

[gdv]

Sorry, I did not update the command. It should be

sudo docker run -v "$PWD"/asgalgw_data:/data algolab/asgal

The latest docker image is at https://hub.docker.com/r/algolab/asgal

Best regards