Hi,

You almost had it. Here is a working example:

ensembl <- useMart(
  'ENSEMBL_MART_ENSEMBL',
  dataset = 'hsapiens_gene_ensembl')

hgncswissprot <- getBM(
  attributes = c('hgnc_symbol', 'uniprotswissprot'),
  filters = c('hgnc_symbol', 'with_hgnc'),
  values = list(c('ACMSD', 'ATP13A2'), TRUE),
  mart = ensembl)

hgncswissprot
  hgnc_symbol uniprotswissprot
1       ACMSD           Q8TDX5
2     ATP13A2           Q9NQ11
3     ATP13A2

Note that we can also have returned to us an entire annotation table, by running this:

annotTable <- getBM(
  attributes = c('hgnc_symbol', 'uniprotswissprot'),
  mart = ensembl)

dim(annotTable)
[1] 33651     2

head(annotTable)
  hgnc_symbol uniprotswissprot
1      MT-ND1           P03886
2      MT-ND2           P03891
3      MT-CO1           P00395
4      MT-CO2           P00403
5     MT-ATP8           P03928
6     MT-ATP6           P00846

Kevin