Release 4

This page is part of the FHIR Specification (v4.0.1: R4 - Mixed Normative and STU) in it's permanent home (it will always be available at this URL). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R4B R4

Extension-observation-geneticsallele.xml

Orders and Observations Work GroupMaturity Level: N/AStandards Status: Informative

Raw XML (canonical form + also see XML Format Specification)

Allele

<?xml version="1.0" encoding="UTF-8"?>

<StructureDefinition xmlns="http://hl7.org/fhir">
  <id value="observation-geneticsAllele"/> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg">
    <valueCode value="oo"/> 
  </extension> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm">
    <valueInteger value="1"/> 
  </extension> 
  <url value="http://hl7.org/fhir/StructureDefinition/observation-geneticsAllele"/> 
  <version value="4.0.1"/> 
  <name value="Allele"/> 
  <status value="draft"/> 
  <date value="2016-03-14"/> 
  <publisher value="Health Level Seven International (Clinical Genomics)"/> 
  <contact> 
    <telecom> 
      <system value="url"/> 
      <value value="http://www.hl7.org/Special/committees/clingenomics"/> 
    </telecom> 
  </contact> 
  <description value="Allele information."/> 
  <fhirVersion value="4.0.1"/> 
  <mapping> 
    <identity value="v2"/> 
    <uri value="http://hl7.org/v2"/> 
    <name value="HL7 v2 Mapping"/> 
  </mapping> 
  <mapping> 
    <identity value="rim"/> 
    <uri value="http://hl7.org/v3"/> 
    <name value="RIM Mapping"/> 
  </mapping> 
  <kind value="complex-type"/> 
  <abstract value="false"/> 
  <context> 
    <type value="element"/> 
    <expression value="Observation"/> 
  </context> 
  <type value="Extension"/> 
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
  <derivation value="constraint"/> 
  <snapshot> 
    <element id="Extension">
      <path value="Extension"/> 
      <short value="Allele"/> 
      <definition value="Allele information."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <condition value="ele-1"/> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), 'value')])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
    </element> 
    <element id="Extension.id">
      <path value="Extension.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension">
      <path value="Extension.extension"/> 
      <slicing> 
        <discriminator> 
          <type value="value"/> 
          <path value="url"/> 
        </discriminator> 
        <description value="Extensions are always sliced by (at least) url"/> 
        <rules value="open"/> 
      </slicing> 
      <short value="Additional content defined by implementations"/> 
      <definition value="May be used to represent additional information that is not part of the basic definition
       of the element. To make the use of extensions safe and manageable, there is a strict set
       of governance  applied to the definition and use of extensions. Though any implementer
       can define an extension, there is a set of requirements that SHALL be met as part of the
       definition of the extension."/> 
      <comment value="There can be no stigma associated with the use of extensions by any application, project,
       or standard - regardless of the institution or jurisdiction that uses or defines the extensions.
        The use of extensions is what allows the FHIR specification to retain a core level of
       simplicity for everyone."/> 
      <alias value="extensions"/> 
      <alias value="user content"/> 
      <min value="0"/> 
      <max value="*"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Name">
      <path value="Extension.extension"/> 
      <sliceName value="Name"/> 
      <short value="Name of allele"/> 
      <definition value="An allele is one of a set of coexisting sequence variants of a gene ([SO:0001023](http://www.sequenc
      eontology.org/browser/current_svn/term/SO:0001023)). This element is the common name for
       the allele. LOINC Code: ([48008-7](http://loinc.org/48008-7))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="v2"/> 
        <map value="N/A"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Name.id">
      <path value="Extension.extension.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Name.extension">
      <path value="Extension.extension.extension"/> 
      <slicing> 
        <discriminator> 
          <type value="value"/> 
          <path value="url"/> 
        </discriminator> 
        <description value="Extensions are always sliced by (at least) url"/> 
        <rules value="open"/> 
      </slicing> 
      <short value="Extension"/> 
      <definition value="An Extension"/> 
      <min value="0"/> 
      <max value="0"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Extension.extension:Name.url">
      <path value="Extension.extension.url"/> 
      <representation value="xmlAttr"/> 
      <short value="identifies the meaning of the extension"/> 
      <definition value="Source of the definition for the extension code - a logical name or a URL."/> 
      <comment value="The definition may point directly to a computable or human-readable definition of the
       extensibility codes, or it may be a logical URI as declared in some other specification.
       The definition SHALL be a URI for the Structure Definition defining the extension."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.url"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="Name"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Name.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <short value="Value of extension"/> 
      <definition value="Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://
      hl7.org/fhir/extensibility.html) for a list)."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.value[x]"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="EBI-AlleleName"/> 
        </extension> 
        <strength value="preferred"/> 
        <description value="EMBL-EBI database of AlleleName."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/allelename"/> 
      </binding> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:State">
      <path value="Extension.extension"/> 
      <sliceName value="State"/> 
      <short value="The level of occurrence of a single DNA sequence variant within a set of chromosomes:
       Heteroplasmic / Homoplasmic / Homozygous / Heterozygous / Hemizygous"/> 
      <definition value="The level of occurrence of a single DNA Sequence Variant within a set of chromosomes.
       Heterozygous indicates the DNA sequence variant is only present in one of the two genes
       contained in homologous chromosomes. Homozygous indicates the DNA Sequence Variant is
       present in both genes contained in homologous chromosomes. Hemizygous indicates the DNA
       Sequence Variant exists in the only single copy of a gene in a non-homologous chromosome
       (the male X and Y chromosome are non-homologous). Hemiplasmic indicates that the DNA Sequence
       Variant is present in some but not all of the copies of mitochondrial DNA. Homoplasmic
       indicates that the DNA Sequence Variant is present in all of the copies of mitochondrial
       DNA. LOINC Code: ([53034-5](http://loinc.org/53034-5))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Extension.extension:State.id">
      <path value="Extension.extension.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:State.extension">
      <path value="Extension.extension.extension"/> 
      <slicing> 
        <discriminator> 
          <type value="value"/> 
          <path value="url"/> 
        </discriminator> 
        <description value="Extensions are always sliced by (at least) url"/> 
        <rules value="open"/> 
      </slicing> 
      <short value="Extension"/> 
      <definition value="An Extension"/> 
      <min value="0"/> 
      <max value="0"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Extension.extension:State.url">
      <path value="Extension.extension.url"/> 
      <representation value="xmlAttr"/> 
      <short value="identifies the meaning of the extension"/> 
      <definition value="Source of the definition for the extension code - a logical name or a URL."/> 
      <comment value="The definition may point directly to a computable or human-readable definition of the
       extensibility codes, or it may be a logical URI as declared in some other specification.
       The definition SHALL be a URI for the Structure Definition defining the extension."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.url"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="State"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:State.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <short value="Value of extension"/> 
      <definition value="Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://
      hl7.org/fhir/extensibility.html) for a list)."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.value[x]"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Frequency">
      <path value="Extension.extension"/> 
      <sliceName value="Frequency"/> 
      <short value="Allele frequency"/> 
      <definition value="A physical quality which inheres to the allele by virtue of the number instances of the
       allele within a population. LOINC Code: ([81258-6](http://loinc.org/81258-6))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Extension.extension:Frequency.id">
      <path value="Extension.extension.id"/> 
      <representation value="xmlAttr"/> 
      <short value="Unique id for inter-element referencing"/> 
      <definition value="Unique id for the element within a resource (for internal references). This may be any
       string value that does not contain spaces."/> 
      <min value="0"/> 
      <max value="1"/> 
      <base> 
        <path value="Element.id"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="string"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="n/a"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Frequency.extension">
      <path value="Extension.extension.extension"/> 
      <slicing> 
        <discriminator> 
          <type value="value"/> 
          <path value="url"/> 
        </discriminator> 
        <description value="Extensions are always sliced by (at least) url"/> 
        <rules value="open"/> 
      </slicing> 
      <short value="Extension"/> 
      <definition value="An Extension"/> 
      <min value="0"/> 
      <max value="0"/> 
      <base> 
        <path value="Element.extension"/> 
        <min value="0"/> 
        <max value="*"/> 
      </base> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <constraint> 
        <key value="ext-1"/> 
        <severity value="error"/> 
        <human value="Must have either extensions or value[x], not both"/> 
        <expression value="extension.exists() != value.exists()"/> 
        <xpath value="exists(f:extension)!=exists(f:*[starts-with(local-name(.), &quot;value&quot;)])"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Extension"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
    </element> 
    <element id="Extension.extension:Frequency.url">
      <path value="Extension.extension.url"/> 
      <representation value="xmlAttr"/> 
      <short value="identifies the meaning of the extension"/> 
      <definition value="Source of the definition for the extension code - a logical name or a URL."/> 
      <comment value="The definition may point directly to a computable or human-readable definition of the
       extensibility codes, or it may be a logical URI as declared in some other specification.
       The definition SHALL be a URI for the Structure Definition defining the extension."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.url"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="Frequency"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Frequency.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <short value="Value of extension"/> 
      <definition value="Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://
      hl7.org/fhir/extensibility.html) for a list)."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.value[x]"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="decimal"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.url">
      <path value="Extension.url"/> 
      <representation value="xmlAttr"/> 
      <short value="identifies the meaning of the extension"/> 
      <definition value="Source of the definition for the extension code - a logical name or a URL."/> 
      <comment value="The definition may point directly to a computable or human-readable definition of the
       extensibility codes, or it may be a logical URI as declared in some other specification.
       The definition SHALL be a URI for the Structure Definition defining the extension."/> 
      <min value="1"/> 
      <max value="1"/> 
      <base> 
        <path value="Extension.url"/> 
        <min value="1"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type">
          <valueUrl value="uri"/> 
        </extension> 
        <code value="http://hl7.org/fhirpath/System.String"/> 
      </type> 
      <fixedUri value="http://hl7.org/fhir/StructureDefinition/observation-geneticsAllele"/> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.value[x]">
      <path value="Extension.value[x]"/> 
      <short value="Value of extension"/> 
      <definition value="Value of extension - must be one of a constrained set of the data types (see [Extensibility](http://
      hl7.org/fhir/extensibility.html) for a list)."/> 
      <min value="0"/> 
      <max value="0"/> 
      <base> 
        <path value="Extension.value[x]"/> 
        <min value="0"/> 
        <max value="1"/> 
      </base> 
      <type> 
        <code value="base64Binary"/> 
      </type> 
      <type> 
        <code value="boolean"/> 
      </type> 
      <type> 
        <code value="canonical"/> 
      </type> 
      <type> 
        <code value="code"/> 
      </type> 
      <type> 
        <code value="date"/> 
      </type> 
      <type> 
        <code value="dateTime"/> 
      </type> 
      <type> 
        <code value="decimal"/> 
      </type> 
      <type> 
        <code value="id"/> 
      </type> 
      <type> 
        <code value="instant"/> 
      </type> 
      <type> 
        <code value="integer"/> 
      </type> 
      <type> 
        <code value="markdown"/> 
      </type> 
      <type> 
        <code value="oid"/> 
      </type> 
      <type> 
        <code value="positiveInt"/> 
      </type> 
      <type> 
        <code value="string"/> 
      </type> 
      <type> 
        <code value="time"/> 
      </type> 
      <type> 
        <code value="unsignedInt"/> 
      </type> 
      <type> 
        <code value="uri"/> 
      </type> 
      <type> 
        <code value="url"/> 
      </type> 
      <type> 
        <code value="uuid"/> 
      </type> 
      <type> 
        <code value="Address"/> 
      </type> 
      <type> 
        <code value="Age"/> 
      </type> 
      <type> 
        <code value="Annotation"/> 
      </type> 
      <type> 
        <code value="Attachment"/> 
      </type> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <type> 
        <code value="Coding"/> 
      </type> 
      <type> 
        <code value="ContactPoint"/> 
      </type> 
      <type> 
        <code value="Count"/> 
      </type> 
      <type> 
        <code value="Distance"/> 
      </type> 
      <type> 
        <code value="Duration"/> 
      </type> 
      <type> 
        <code value="HumanName"/> 
      </type> 
      <type> 
        <code value="Identifier"/> 
      </type> 
      <type> 
        <code value="Money"/> 
      </type> 
      <type> 
        <code value="Period"/> 
      </type> 
      <type> 
        <code value="Quantity"/> 
      </type> 
      <type> 
        <code value="Range"/> 
      </type> 
      <type> 
        <code value="Ratio"/> 
      </type> 
      <type> 
        <code value="Reference"/> 
      </type> 
      <type> 
        <code value="SampledData"/> 
      </type> 
      <type> 
        <code value="Signature"/> 
      </type> 
      <type> 
        <code value="Timing"/> 
      </type> 
      <type> 
        <code value="ContactDetail"/> 
      </type> 
      <type> 
        <code value="Contributor"/> 
      </type> 
      <type> 
        <code value="DataRequirement"/> 
      </type> 
      <type> 
        <code value="Expression"/> 
      </type> 
      <type> 
        <code value="ParameterDefinition"/> 
      </type> 
      <type> 
        <code value="RelatedArtifact"/> 
      </type> 
      <type> 
        <code value="TriggerDefinition"/> 
      </type> 
      <type> 
        <code value="UsageContext"/> 
      </type> 
      <type> 
        <code value="Dosage"/> 
      </type> 
      <type> 
        <code value="Meta"/> 
      </type> 
      <constraint> 
        <key value="ele-1"/> 
        <severity value="error"/> 
        <human value="All FHIR elements must have a @value or children"/> 
        <expression value="hasValue() or (children().count() &gt; id.count())"/> 
        <xpath value="@value|f:*|h:div"/> 
        <source value="http://hl7.org/fhir/StructureDefinition/Element"/> 
      </constraint> 
      <isModifier value="false"/> 
      <isSummary value="false"/> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
  </snapshot> 
  <differential> 
    <element id="Extension">
      <path value="Extension"/> 
      <short value="Allele"/> 
      <definition value="Allele information."/> 
      <min value="0"/> 
      <max value="1"/> 
    </element> 
    <element id="Extension.extension:Name">
      <path value="Extension.extension"/> 
      <sliceName value="Name"/> 
      <short value="Name of allele"/> 
      <definition value="An allele is one of a set of coexisting sequence variants of a gene ([SO:0001023](http://www.sequenc
      eontology.org/browser/current_svn/term/SO:0001023)). This element is the common name for
       the allele. LOINC Code: ([48008-7](http://loinc.org/48008-7))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="Extension"/> 
      </type> 
      <mapping> 
        <identity value="v2"/> 
        <map value="N/A"/> 
      </mapping> 
      <mapping> 
        <identity value="rim"/> 
        <map value="N/A"/> 
      </mapping> 
    </element> 
    <element id="Extension.extension:Name.extension">
      <path value="Extension.extension.extension"/> 
      <max value="0"/> 
    </element> 
    <element id="Extension.extension:Name.url">
      <path value="Extension.extension.url"/> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="Name"/> 
    </element> 
    <element id="Extension.extension:Name.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <min value="1"/> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
      <binding> 
        <extension url="http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName">
          <valueString value="EBI-AlleleName"/> 
        </extension> 
        <strength value="preferred"/> 
        <description value="EMBL-EBI database of AlleleName."/> 
        <valueSet value="http://hl7.org/fhir/ValueSet/allelename"/> 
      </binding> 
    </element> 
    <element id="Extension.extension:State">
      <path value="Extension.extension"/> 
      <sliceName value="State"/> 
      <short value="The level of occurrence of a single DNA sequence variant within a set of chromosomes:
       Heteroplasmic / Homoplasmic / Homozygous / Heterozygous / Hemizygous"/> 
      <definition value="The level of occurrence of a single DNA Sequence Variant within a set of chromosomes.
       Heterozygous indicates the DNA sequence variant is only present in one of the two genes
       contained in homologous chromosomes. Homozygous indicates the DNA Sequence Variant is
       present in both genes contained in homologous chromosomes. Hemizygous indicates the DNA
       Sequence Variant exists in the only single copy of a gene in a non-homologous chromosome
       (the male X and Y chromosome are non-homologous). Hemiplasmic indicates that the DNA Sequence
       Variant is present in some but not all of the copies of mitochondrial DNA. Homoplasmic
       indicates that the DNA Sequence Variant is present in all of the copies of mitochondrial
       DNA. LOINC Code: ([53034-5](http://loinc.org/53034-5))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="Extension"/> 
      </type> 
    </element> 
    <element id="Extension.extension:State.extension">
      <path value="Extension.extension.extension"/> 
      <max value="0"/> 
    </element> 
    <element id="Extension.extension:State.url">
      <path value="Extension.extension.url"/> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="State"/> 
    </element> 
    <element id="Extension.extension:State.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <min value="1"/> 
      <type> 
        <code value="CodeableConcept"/> 
      </type> 
    </element> 
    <element id="Extension.extension:Frequency">
      <path value="Extension.extension"/> 
      <sliceName value="Frequency"/> 
      <short value="Allele frequency"/> 
      <definition value="A physical quality which inheres to the allele by virtue of the number instances of the
       allele within a population. LOINC Code: ([81258-6](http://loinc.org/81258-6))."/> 
      <min value="0"/> 
      <max value="1"/> 
      <type> 
        <code value="Extension"/> 
      </type> 
    </element> 
    <element id="Extension.extension:Frequency.extension">
      <path value="Extension.extension.extension"/> 
      <max value="0"/> 
    </element> 
    <element id="Extension.extension:Frequency.url">
      <path value="Extension.extension.url"/> 
      <type> 
        <code value="uri"/> 
      </type> 
      <fixedUri value="Frequency"/> 
    </element> 
    <element id="Extension.extension:Frequency.value[x]">
      <path value="Extension.extension.value[x]"/> 
      <min value="1"/> 
      <type> 
        <code value="decimal"/> 
      </type> 
    </element> 
    <element id="Extension.url">
      <path value="Extension.url"/> 
      <fixedUri value="http://hl7.org/fhir/StructureDefinition/observation-geneticsAllele"/> 
    </element> 
    <element id="Extension.value[x]">
      <path value="Extension.value[x]"/> 
      <min value="0"/> 
      <max value="0"/> 
    </element> 
  </differential> 
</StructureDefinition>

Usage note: every effort has been made to ensure that the examples are correct and useful, but they are not a normative part of the specification.