diff --git a/java/src/org/broadinstitute/sting/gatk/refdata/rodGFF.java b/java/src/org/broadinstitute/sting/gatk/refdata/rodGFF.java
index f08409da0..77b76dda3 100644
--- a/java/src/org/broadinstitute/sting/gatk/refdata/rodGFF.java
+++ b/java/src/org/broadinstitute/sting/gatk/refdata/rodGFF.java
@@ -110,7 +110,7 @@ public class rodGFF extends BasicReferenceOrderedDatum implements AllelicVariant
     }
 
     public String toSimpleString() {
-        return String.format("%s", feature);
+        return String.format("chip-genotype: %s", feature);
     }