diff --git a/modules/Bio/EnsEMBL/Slice.pm b/modules/Bio/EnsEMBL/Slice.pm
index a8e2881b14a5b95f01566d0687bd3e4e2d902ef5..a48606af2dedde340b0b09df3a4b33ca21b65f27 100644
--- a/modules/Bio/EnsEMBL/Slice.pm
+++ b/modules/Bio/EnsEMBL/Slice.pm
@@ -806,11 +806,10 @@ sub is_chromosome {
                     |clone
                     |contig
                     |genescaffold
-                    |group
                     |reftig
                     |supercontig
                     |ultracontig        
-                    /x) or ( $coord_system !~ /^chromosome$/i )) {
+                    /x) or ( $coord_system !~ /^chromosome$/i && $coord_system !~ /^group$/i ) ) {
     return 0;
   }