Unfortunately our reads have the barcodes already removed, but this is a very interesting script nonetheless.
Has anyone used Bioscope 1.2 to split barcoded and pooled SOLiD sequence reads? E.g. if i start with one .csfasta file containing six different barcodes I want to be able to split them into six different .csfasta files, each containing only one barcode.
I realise i can probably script this splitting process myself, but i would like to know how this can be achieved using Bioscope.
Thanks!
3 answers
Members of the Pugh Lab have developed a barcode splitter for the SOLiD platform. It is a perl script that you can get from:
http://bcc.bx.psu.edu/static/sep_tag_by_color_barcode-v1.1.pl
One neat feature is that it allows mismatches.
You may be able to generate a new file with the barcodes added to the beginning of each read then the script would work.
OK that is probably worth trying.
One feature that I am exploring for the new version of BioStar is to integrate it with a source code version control system to allow people to share code that may be longer than a small snippet.
I hadn't heard about Bioscope, it seems to be a complex commercial suite by Applied Biosystems, but given there is the Fastx toolkit with the barcode splitter on Galaxy, it's maybe not necessary to use such a complex tool anyway.
Edit: Caveat: Fastx might not be able to process in colorspace, does someone know?
My recommendation: keep it simple, you possibly don't need to bother with such a complex (some people might call it bloated) tool as the one you are mentioning that might cost you license fees for trivial tasks.
Just as an aside point: In my opinion the vendors should focus more on their strength in producing rock-'solid' instruments and not on building software suits promising lofty "analysis without bioinformatics knowledge", because they cannot really offer you that, as they lack largely the programming and bioinformatics expertise themselves.
In case it helps, Galaxy URL: http://main.g2.bx.psu.edu/
Thanks i have noticed fastX before, but i don't think it handles SOLiD colour space reads...
Doesn't it? I didn't try it for that, ducumentation just states it handles fasta and fastq. Last resort: to convert to letter-space before splitting, but ofc you might want to align in color-space...
I'm currently setting a local installation of Galaxy on our cluster, and I haven't found a way of splitting by barcodes using Galaxy only. as far as I understand the issue, we will have to pre-process our csfasta files with a custom barcode splitter such as the ones described here, and then feed the analysis software (galaxy or any other) with the splitted csfasta files.
@michael: BioScope is the free (until now) tool from Applied that claims to be very easy to install and use. but I can't really talk about its usability yet because we've waiting 2 month to have it installed ;)
sorry, I just came through the fastx instructions on how to integrate their toolkit into Galaxy. FYI: http://hannonlab.cshl.edu/fastx_toolkit/galaxy.html
In the end i have written a script to answer my own question, but thanks for the previous answers!
Basically my script pairs the core read id (number_number_number) of the sequence and qualities scores with the barcode id. I made the decision to allow missed colours (designated by '.' in the sequence and '-1' in the quality scores) and one wrong colour call. In both cases there has to be only one unambiguous match to one of the sixteen 5mer barcodes.
I am testing it at the moment, but if anyone is interested in taking a look i am happy to make it available.
Hi Ian, could you share the script with me please? The email address is my username here @gmail.com.
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Thank you everyone for your comments. In the end i wrote my own script to split the barcoded reads. Basically it pairs the core read id (number_number_number) of the sequence and qualities scores with the barcode id.
I made the decision to allow missed colours (designated by '.' in the sequence and '-1' in the quality scores) and one wrong colour call. In both cases there has to be only one unambiguous match to one of the sixteen 5mer barcodes.
I am testing it at the moment, but if anyone is interested in taking a look i am happy to make it available.