Version 2.77

Term Description

Copy number >36 is considered abnormal and an indication of Huntington disease (HD).
Source: Regenstrief LOINC

Part Description

LP19792-8   HTT gene.CAG repeats
Expansion of the CAG triplet repeat in the HTT gene (also known as IT15 or HD gene) causes Huntington disease (HD), a progressive brain disorder that causes uncontrolled movements, emotional changes, and loss of cognition. The HTT gene is located on chromosome 4 and position p16.3. The expanded CAG segment leads to the production of an abnormally long version of the huntingtin protein. People with Huntington disease have 36 to more than 120 CAG repeats. People with 36 to 39 CAG repeats may or may not develop the signs and symptoms of Huntington disease, while people with 40 or more repeats almost always develop the disorder. Source: Genetic Home Reference, National Library of Medicine, HTT gene

Fully-Specified Name

HTT gene.CAG repeats

Additional Names

Short Name
HTT gene CAG Rpt Bld/T Ql
Display Name
HTT gene CAG repeats Molgen Ql (Bld/Tiss)
Consumer Name Alpha Get Info
HTT gene CAG Repeats, Blood or tissue specimen

Example Answer List: LL2303-7

Source: Regenstrief LOINC
Answer Code Score Answer ID
Not Expanded LA19353-4
Intermediate LA16550-8
Reduced penetrance LA19354-2
Expanded LA19352-6

Basic Attributes

First Released
Version 1.0m
Last Updated
Version 2.73
Change Reason
Changed gene name from HD to HTT, the current (2012) approved HUGO gene name. June 2015: Changed Property from Arb (Arbitrary) to 'Threshold' since the results (e.g. positive, intermediate, negative) is based on the number of nucleotide repeats. Moved term from Class MOLPATH.TRINUC to MOLPATH.NUCREPEAT, a Class used to group together observations for nucleotide repeats.; The PrThr property is used for LOINC terms whose results are reported using an ordered categorical scale, regardless of whether or not an internal threshold was used to make that determination. This change was approved by the Laboratory LOINC Committee in June 2016.
Order vs. Observation
Common Test Rank Get Info

Member of these Panels

LOINC Long Common Name
53783-7 HTT gene mutation panel - Blood or Tissue by Molecular genetics method

Language Variants Get Info

Tag Language Translation
es-AR Spanish (Argentina) gen HD.repeticiones CAG:arbitrario:punto en el tiempo:sangre entera/tejido:ordinal:genética molecular
es-ES Spanish (Spain) Repeticiones CAG del gen HTT:PrThr:Punto temporal:Sangre o tejido:Ord:Genética molecular
es-MX Spanish (Mexico) HTT gene.CAG repeticiones:Presencia o umbral:Punto temporal:Sangre o tejido:Ordinal:Genética molecular
fr-FR French (France) HTT gène répétitions CAG:Présence/Seuil:Ponctuel:Sang/Tissu:Qualitatif:Biologie moléculaire
it-IT Italian (Italy) HD gene.CAG ripetizioni:PrThr:Pt:Sangue/Tess:Ord:Molgen
Synonyms: Gene HD Genetica molecolare Patologia molecolare Presenza o Soglia Punto nel tempo (episodio) Ripetizione nucleotidi Ripetizioni CAG del gene HD Sangue Sangue o Tessuto Tessuto & Strisci
ko-KR Korean (Korea, Republic Of) HD 유전자.CAG 반복:임의적분:검사시점:전혈/조직:순위척도:분자유전
nl-NL Dutch (Netherlands) HTT-gen.CAG repeats:aanwezigheid:moment:bloed of weefsel:ordinaal:moleculair genetisch onderzoek
Synonyms: HTT gen HTT gen.CAG repeats molgen
pt-BR Portuguese (Brazil) HD gene.CAG repetições:Arb:Pt:Sg/Tecido:Ord:Genética molecular
Synonyms: ; HD gene CAG Rpt; Huntington disease; IT15; Huntington chorea; Arbitrary; Point in time; Random; Bld/T; Tissue; Bld/T; Blood; WB; Whole blood; Ql; Ordinal; QL; Qualitative; Qual; Screen; PCR; Molecular genetics; Repeat; MOLPATH.TRINUCLEOTIDE REPEATS; MOLPATH.TRINUCLEOTIDE REPEATS; Molecular pathology
ru-RU Russian (Russian Federation) HTT ген.CAG повторы:PrThr:ТчкВрм:Кр/Тк:Пор:МолГен
Synonyms: Кровь Кровь или Ткань Порядковый Ткань и мазки Точка во времени;Момент
tr-TR Turkish (Turkey) HD geni.CAG tekrarları:MevcEşik:Zmlı:Kan/Dk:Srl:Molgen
Synonyms: Mevcut
zh-CN Chinese (China) HTT 基因.CAG 重复序列:存在情况或阈值:时间点:全血/组织:序数型:分子遗传学类实验室方法
Synonyms: HD 基因.CAG 重复序列;Huntington 舞蹈病;IT15;亨廷登病;亨廷登舞蹈病;亨廷顿病;亨廷顿舞蹈病;哈特克病;哈特克舞蹈病;杭廷顿氏舞蹈症;HD 基因 Huntington 舞蹈病;IT15;亨廷登病;亨廷登舞蹈病;亨廷顿病;亨廷顿舞蹈病;哈特克病;哈特克舞蹈病;杭廷顿氏舞蹈症;HD 基因 依次型;分类顺序型;定性的;序数型(或称等级型);性质上的;有序型;有序性分类应答;有序性分类结果;秩次型;等级型;筛查;顺序型 全血或组织;血液/组织;血液或组织 分子病理学;分子病理学试验 分子遗传学;分子遗传学方法;分子遗传学类方法;分子遗传学类检验方法;包括 RFL、PCR 及其他方法在内,用于在分子基础上检测遗传属性的方法的大类;聚合酶链反应;聚合酶链式反应 存在情况;存在;存在与否;是否存在;阈值;界值;界限;阀值;临界值;存在情况(存在、存在与否、是否存在)或阈值(界值、界限、阀值、临界值) 时刻;随机;随意;瞬间 未作说明的组织;组织;组织 & 涂片 血;血液 遗传基因;遗传因子;吉恩;生物基因 重复

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