diff --git a/schema/vrs/vrs-source.yaml b/schema/vrs/vrs-source.yaml
index 107f4358..18fcdca0 100644
--- a/schema/vrs/vrs-source.yaml
+++ b/schema/vrs/vrs-source.yaml
@@ -343,6 +343,17 @@ $defs:
         enum:
           - aa
           - na
+      sequence:
+        type:
+          $ref: "#/$defs/SequenceString"
+        description: >-
+          A :ref:`SequenceString` that is a literal representation of the referenced sequence.
+      moleculeType:
+        type: string
+        enum:
+          - genomic
+          - transcript
+          - protein
       circular:
         type: boolean
         description: >-