diff --git a/modules/Bio/EnsEMBL/Translation.pm b/modules/Bio/EnsEMBL/Translation.pm
index d4955f5004b1f397e7b9a5e2a4301ccc2c82cc81..99bace42d880c5acfc957a4f31f4f019bcd0e048 100755
--- a/modules/Bio/EnsEMBL/Translation.pm
+++ b/modules/Bio/EnsEMBL/Translation.pm
@@ -849,7 +849,9 @@ sub seq {
 
     my $canonical_translation = $transcript->translation();
     my $is_alternative;
-
+    if(!$canonical_translation) {
+	throw "Transcript does not have a canonical translation";
+    }
     if (    defined( $canonical_translation->stable_id() )
          && defined( $self->stable_id() ) )
     {