diff --git a/modules/Bio/EnsEMBL/IdMapping/StableIdGenerator/EnsemblGeneric.pm b/modules/Bio/EnsEMBL/IdMapping/StableIdGenerator/EnsemblGeneric.pm
index ad1b5eec27ef90c0ef521d01c04b4aeda7ec8b65..ac859f5ea233e17cab04da1c206be8e05d94efc2 100644
--- a/modules/Bio/EnsEMBL/IdMapping/StableIdGenerator/EnsemblGeneric.pm
+++ b/modules/Bio/EnsEMBL/IdMapping/StableIdGenerator/EnsemblGeneric.pm
@@ -305,7 +305,9 @@ sub calculate_version {
 
     # increment version if translation sequence changed
     # Can happen if Havana move initiation start site or stop codon
-    if ($s_obj->translation->seq ne $t_obj->translation->seq) { $change = 1; }
+    if ($s_obj->translation and $t_obj->translation) {
+         if ($s_obj->translation->seq ne $t_obj->translation->seq) { $change = 1; }
+    }
 
     # Look for changes on the region
     if ( $s_obj->seq_region_name() ne $t_obj->seq_region_name() ) { $change = 1 }