<p>Hi,</p>

<p>I have an expression profile dataset with a list of genes and normalized expression data. What i want is to only look at genes on the Y chromosome.</p>

<p>Most of the gene annotation packages with R or otherwise look for gene ids/probe-set ID to map to chromosomal information. Can you please help me out with a way to extract chromosomal information ( preferably through an R package) with only the gene names ?</p>

<p>Thanks !</p>

<p>The trick is to use the "org" package for your organism.  Here I show human, but you can substitute....</p>

<pre><code>library(org.Hs.eg.db)
symbols = c('BRCA1','TP53','GAPDH')
select(org.Hs.eg.db,keys=symbols,cols=c('SYMBOL','CHR'),keytype='SYMBOL')
</code></pre>

<p>Which will return:</p>

<pre><code>  SYMBOL CHR
1  BRCA1  17
2   TP53  17
3  GAPDH  12
</code></pre>
