diff --git a/annotation/functions.scm b/annotation/functions.scm
index b64d24f..0c26889 100644
--- a/annotation/functions.scm
+++ b/annotation/functions.scm
@@ -481,31 +481,63 @@ in the specified namespaces."
 
 ;; ------------------------------------------------------
 
-;; Gene interactors for genes in the pathway
-(define do-pathway-gene-interactors
-  (lambda (pw)
-  (run-query (BindLink
-    (VariableList
-     (TypedVariable (VariableNode "$g1") (Type 'GeneNode))
-     (TypedVariable (VariableNode "$g2") (Type 'GeneNode))
-     (TypedVariable (VariableNode "$p1") (Type 'MoleculeNode))
-     (TypedVariable (VariableNode "$p2") (Type 'MoleculeNode)))
-   (AndLink
-     (MemberLink (VariableNode "$p1") pw)
-     (MemberLink (VariableNode "$p2") pw)
-     (EvaluationLink (PredicateNode "expresses") (ListLink (VariableNode "$g1") (VariableNode "$p1")))
-     (EvaluationLink (PredicateNode "expresses") (ListLink (VariableNode "$g2") (VariableNode "$p2")))
-     (EvaluationLink (PredicateNode "interacts_with") (ListLink (VariableNode "$g1") (VariableNode "$g2")))
-   )
-  (ExecutionOutputLink
-    (GroundedSchemaNode "scm: generate-interactors")
-		  (ListLink
-        pw
-        (VariableNode "$g1")
-		    (VariableNode "$g2")
-		  ))
-  ))
-))
+(define (generate-interactors path var1 var2)
+	; (biogrid-reported-pathways) is a cache of the interactions that have
+	; already been handled. Defined in util.scm and cleared in main.scm.
+	(if (or (equal? var1 var2)
+			((biogrid-reported-pathways) (Set var1 var2))) #f
+		(let ([output (find-pubmed-id var1 var2)])
+			(if (null? output)
+				(EvaluationLink
+					(PredicateNode "interacts_with")
+					(ListLink var1 var2))
+				(EvaluationLink
+					(PredicateNode "has_pubmedID")
+					(ListLink
+						(EvaluationLink
+							(PredicateNode "interacts_with")
+							(ListLink var1 var2))
+						output)))))
+)
+
+(define (do-pathway-gene-interactors pw)
+"
+  Gene interactors for genes in the pathway.
+
+  This finds all pentagons, where two proteins appear on the same
+  pathway, the genes expressing those proteins are known, and the
+  two genes are interacting. That is,
+
+    pathway <--is-in-- protein-1 <--expresses-- gene-1
+    pathway <--is-in-- protein-2 <--expresses-- gene-2
+    gene-1 <--interacts--> gene-2
+"
+   ; Find all interaction
+   (define gene-pentagons
+      (run-query (Get
+         (VariableList
+            (TypedVariable (Variable "$g1") (Type 'GeneNode))
+            (TypedVariable (Variable "$g2") (Type 'GeneNode))
+            (TypedVariable (Variable "$p1") (Type 'MoleculeNode))
+            (TypedVariable (Variable "$p2") (Type 'MoleculeNode)))
+         (And
+            (Member (Variable "$p1") pw)
+            (Member (Variable "$p2") pw)
+            (Evaluation (Predicate "expresses")
+               (List (Variable "$g1") (Variable "$p1")))
+            (Evaluation (Predicate "expresses")
+               (List (Variable "$g2") (Variable "$p2")))
+            (Evaluation (Predicate "interacts_with")
+               (List (Variable "$g1") (Variable "$g2")))))))
+
+   (filter-map
+      (lambda (gene-path)
+         (define g1 (gar gene-path))
+         (define g2 (gdr gene-path))
+         (cog-delete gene-path) ; get rid of unused ListLink
+         (generate-interactors pw g1 g2))
+      gene-pentagons)
+)
 
 ;; Cache previous results, so that they are not recomputed again,
 ;; if the results are already known. Note that this function accounts
@@ -696,25 +728,6 @@ in the specified namespaces."
   )
 )
 
-(define-public (generate-interactors path var1 var2)
-	; (biogrid-reported-pathways) is a cache of the interactions that have
-	; already been handled. Defined in util.scm and cleared in main.scm.
-	(if (or (equal? var1 var2)
-			((biogrid-reported-pathways) (Set var1 var2))) '()
-		(let ([output (find-pubmed-id var1 var2)])
-			(if (null? output)
-				(EvaluationLink
-					(PredicateNode "interacts_with")
-					(ListLink var1 var2))
-				(EvaluationLink
-					(PredicateNode "has_pubmedID")
-					(ListLink
-						(EvaluationLink
-							(PredicateNode "interacts_with")
-							(ListLink var1 var2))
-						output)))))
-)
-
 ;; ------------------------------------------------------
 (define (do-find-pubmed-id gene-set)
 "