Entering edit mode
Dear Loren,
I don't understand why you would want to read in a gmt file from the
Broad
Institute rather than use the curated rdata files that we provide for
use
with romer. The raw gmt files contain a mix of gene symbols of
different
species and a mix of official and non-official symbols. So one can't
expect to match the symbols you get from a raw gmt file to your own
data
with any reliability. To construct the rdata files, we have carefully
converted all gene aliases to official symbols and have mapped mouse
to
human and human to mouse orthologs.
This is the reason why we don't provide a read.gmt() function in
limma, or
a pre-made pipeline from the GSEABase read functions. We don't want
you
to get unreliable results simply because the gene symbols haven't been
curated.
Best wishes
Gordon
> Date: Tue, 04 May 2010 07:43:46 -0700
> From: Loren Engrav <engrav at="" u.washington.edu="">
> To: rbioc <bioconductor at="" stat.math.ethz.ch="">
> Subject: Re: [BioC] Romer and symbols2indices query
> Message-ID: <c80580b2.27d83%engrav at="" u.washington.edu="">
> Content-Type: text/plain; charset="US-ASCII"
>
> Thank you, got it
>
> Downloading rdata objects saves reading them into an rdata object,
cool
>
> But for interest, in R/GSA there is
> GSA.read.gmt(filename.gmt) to read in a .gmt file
>
> Does limma or romer have an equivalent function?
>
>
>> From: Matthew Ritchie <mritchie at="" wehi.edu.au="">
>> Date: Tue, 4 May 2010 14:44:23 +1000 (EST)
>> To: Loren Engrav <engrav at="" u.washington.edu="">
>> Cc: rbioc <bioconductor at="" stat.math.ethz.ch="">
>> Subject: Re: [BioC] Romer and symbols2indices query
>>
>> Dear Loren,
>>
>> You can find rdata objects of the Broad's MSigDB gene sets at
>>
>> http://bioinf.wehi.edu.au/software/MSigDB/index.html
>>
>> You are right, the 'symbols' argument in the function
symbols2indicies()
>> are the gene symbols corresponding to the probes from your
microarray
>> data.
>>
>> For example, to use the human C2 collection, download the rdata
file, then
>> run the following.
>>
>> load("human_c2.rdata")
>> c2 = symbols2indices(Hs.gmtl.c2, symbols)
>>
>> (this assumes 'symbols' is a vector containing the gene symbols
from your
>> array data)
>>
>> Best wishes,
>>
>> Matt
>>
>>> Have done GSEA and GSA for set enrichment and am setting out to
try romer
>>> and have probably "simple" question
>>>
>>> To get the Broad set into a list of indices there is
>>> symbols2indices(gmtl.official, symbols) but
>>>
>>> 1)how do I get the Broad set into gmtl.official? And
>>> 2)is symbols a vector of MY probe sets of interest?
>>>
>>> I checked gmane and found only one comment about romer
>>> Also checked limma reference pdf
>>>
>>> Thank you
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