| Source Element | Usage | Target |
| SubstanceNucleicAcid | UseExtension | http://hl7.org/fhir/5.0/StructureDefinition/extension-SubstanceNucleicAcid |
| SubstanceNucleicAcid.id | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.meta | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.implicitRules | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.language | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.text | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.contained | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.extension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.modifierExtension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.sequenceType | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.numberOfSubunits | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.areaOfHybridisation | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.oligoNucleotideType | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.id | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.extension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.modifierExtension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.subunit | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sequence | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.length | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sequenceAttachment | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.fivePrime | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.threePrime | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.id | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.extension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.modifierExtension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.connectivity | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.identifier | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.name | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.linkage.residueSite | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.id | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.extension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.modifierExtension | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.identifier | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.name | UseExtensionFromAncestor | - |
| SubstanceNucleicAcid.subunit.sugar.residueSite | UseExtensionFromAncestor | - |