When we look at the filters of ensembl in biomart package in R, it shows two options for the microarray platform hg_u133a:
affy_hg_u133a: Affy hg u133a probeset ID(s) [e.g. 200874_s_at] with_affy_hg_u133a: with Affymetrix Microarray hg u133a probeset ID(s)
the same happens for other microarrays.
The code to get filters is shown bellow:
library(biomaRt) ensembl = useMart(biomart ="ENSEMBL_MART_ENSEMBL",dataset="hsapiens_gene_ensembl") filters = listFilters(ensembl)
Does someone know what is the difference between affy_hg_u133a and with_affy_hg_u133a?