How can I convert gene names (hgnc_symbol) to Ensemble IDs in R? “bioconductor-biomaRt”

Question

I have a list of genes as rownames of my eset and I want to convert them to Ensembl gene ID. I used getGene in bioMart package but it took the same name twice for some genes! here is a small example for my code:

library (biomaRt)
rownames(eset)
[1] "EPC1"   "MYO3A"  "PARD3"  "ATRNL1" "GDF2"   "IL10RA" "GAD2"   "CCDC6"

getGene(rownames(eset),type='hgnc_symbol',mart)[c(1,9)]

# [1] is the hgnc_symbol to recheck the matched data
# [9] is the ensemble_gene_id

   hgnc_symbol ensembl_gene_id
    1      ATRNL1 ENSG00000107518
    2       CCDC6 ENSG00000108091
    3        EPC1 ENSG00000120616
    4        GAD2 ENSG00000136750
    5        GDF2 ENSG00000263761
    6      IL10RA ENSG00000110324
    7      IL10RA         LRG_151
    8       MYO3A ENSG00000095777
    9       PARD3 ENSG00000148498

As you can see there are two entries for "IL10RA" in the hgnc_symbol column; but I only had one "IL10RA" in the rownames(eset); this causes a problem at the end when I wanted to add the Ensembl_ID to the fData(eset)! How can I solve this problem? to have result like this:

 hgnc_symbol ensembl_gene_id
    1      ATRNL1 ENSG00000107518
    2       CCDC6 ENSG00000108091
    3        EPC1 ENSG00000120616
    4        GAD2 ENSG00000136750
    5        GDF2 ENSG00000263761
    6      IL10RA ENSG00000110324
    7       MYO3A ENSG00000095777
    8       PARD3 ENSG00000148498

Thanks in advance,

Answer 1

I've found the solution by !duplicated in the eset. Something like this:

g_All <- getGene(id = rownames(eset)),type='hgnc_symbol',mart)
g_All <- g_All[!duplicated(g_All[,1]),]