diff --git a/R/bio/diffex_commons.R b/R/bio/diffex_commons.R
index b63d5aff4aad06108ae1fcb2de76e32e82e740da..a7fafb515cb71669f7462f097c1f1b43b1b445d5 100644
--- a/R/bio/diffex_commons.R
+++ b/R/bio/diffex_commons.R
@@ -33,6 +33,10 @@ guess_mart <- function(gene_id){
     }
 }
 
+get_ensembl_build <- function(){
+    biomaRt::listMarts() %>% as.data.frame() %>% filter(biomart=="ensembl") %>% with(str_match(version, " ([0-9]*) ")) %>% subset(select=2)
+}
+
 guess_pathview_species <- function(gene_id){
     an_id <-gene_id[1]