diff --git a/release-notes.txt b/release-notes.txt
index 1791cc79d1..18671a7496 100644
--- a/release-notes.txt
+++ b/release-notes.txt
@@ -1,5 +1,9 @@
 {{$NEXT}}
 
+ * Fixed off-by-one error in Wiggle track display code: wiggle data
+   was incorrectly displayed shifted one base to the left of its
+   proper position.  Thanks to Steffi Geisen for noticing this.
+
  * Fixed bug in which reference-sequence selection box did not
    automatically update in all situations to reflect the current
    reference sequence.
diff --git a/src/JBrowse/View/Track/Wiggle.js b/src/JBrowse/View/Track/Wiggle.js
index 992d10ea5c..75c864789b 100644
--- a/src/JBrowse/View/Track/Wiggle.js
+++ b/src/JBrowse/View/Track/Wiggle.js
@@ -191,8 +191,8 @@ var Wiggle = declare( CanvasTrack,
                             var score = f.get('score');
                             var rTop = toY( score );
                             if( rTop <= canvasHeight ) {
-                                var rWidth = Math.ceil(( f.get('end') - f.get('start') + 1 ) * scale );
-                                var rLeft  = Math.floor(( f.get('start')-1 - leftBase ) * scale );
+                                var rWidth = Math.ceil(( f.get('end') - f.get('start') ) * scale );
+                                var rLeft  = Math.floor(( f.get('start') - leftBase ) * scale );
                                 this._updatePixelScores( pixelScores, rLeft, rWidth, score );
                                 if( rTop <= originY ) {
                                     // bar goes upward