diff --git a/paxtools-core/src/main/java/org/biopax/paxtools/impl/level3/NucleicAcidRegionReferenceImpl.java b/paxtools-core/src/main/java/org/biopax/paxtools/impl/level3/NucleicAcidRegionReferenceImpl.java
index <HASH>..<HASH> 100644
--- a/paxtools-core/src/main/java/org/biopax/paxtools/impl/level3/NucleicAcidRegionReferenceImpl.java
+++ b/paxtools-core/src/main/java/org/biopax/paxtools/impl/level3/NucleicAcidRegionReferenceImpl.java
@@ -29,7 +29,7 @@ public abstract class NucleicAcidRegionReferenceImpl extends NucleicAcidReferenc
 	}
 
 
-	@ManyToMany(targetEntity = NucleicAcidRegionReferenceImpl.class,
+	@ManyToMany(targetEntity = NucleicAcidReferenceImpl.class,
 	            mappedBy = "subRegion", cascade = {CascadeType.ALL})
 	public Set<NucleicAcidReference> getSubRegionOf()
 	{
Bug fixed in the @ManyToMany mapping (wrong target class in the annotation)