diff --git a/Lib/fontTools/varLib/featureVars.py b/Lib/fontTools/varLib/featureVars.py
index de2808db9..4caf30a22 100644
--- a/Lib/fontTools/varLib/featureVars.py
+++ b/Lib/fontTools/varLib/featureVars.py
@@ -342,7 +342,7 @@ def buildGSUB():
     langrec = ot.LangSysRecord()
     langrec.LangSys = ot.LangSys()
     langrec.LangSys.ReqFeatureIndex = 0xFFFF
-    langrec.LangSys.FeatureIndex = [0]
+    langrec.LangSys.FeatureIndex = []
     srec.Script.DefaultLangSys = langrec.LangSys
 
     gsub.ScriptList.ScriptRecord.append(srec)