diff --git a/python/snpSelector.py b/python/snpSelector.py
index e01725e3e..a0f555c4a 100755
--- a/python/snpSelector.py
+++ b/python/snpSelector.py
@@ -619,7 +619,7 @@ def main():
 
     if OPTIONS.truth <> None:
         truthVCF = OPTIONS.truth
-        readTruth(truthVCF)
+        TRUTH_CALLS = readTruth(truthVCF)
 
     if len(args) > 1:
         truthVCF = args[1]