Retrieve detailed gene descriptions
Description of how to use biomaRt here. Filter by your list of gene IDs. Get the descriptions etc as attributes. Eg:

&gt; library(biomaRt)
&gt; ensembl = useEnsembl(biomart="ensembl", dataset="hsapiens_gene_ensembl")
&gt; IDs &lt;- c("BRCA2","BRAF")
genedesc &lt;- getBM(attributes=c('external_gene_name','description'), filters = 'external_gene_name', values = IDs, mart =ensembl)
&gt; genedesc
  external_gene_name                                                                      description
1               BRAF B-Raf proto-oncogene, serine/threonine kinase [Source:HGNC Symbol;Acc:HGNC:1097]
2              BRCA2                  BRCA2, DNA repair associated [Source:HGNC Symbol;Acc:HGNC:1101]