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Aliases for HTT Gene

Aliases for HTT Gene

  • Huntingtin 2 3 5
  • Huntington Disease Protein 3 4
  • IT15 3 4
  • HD 3 4
  • Huntingtin (Huntington Disease) 2
  • HD Protein 4

External Ids for HTT Gene

Previous HGNC Symbols for HTT Gene

  • HD

Previous GeneCards Identifiers for HTT Gene

  • GC04P003046
  • GC04P003014

Summaries for HTT Gene

Entrez Gene Summary for HTT Gene

  • Huntingtin is a disease gene linked to Huntington's disease, a neurodegenerative disorder characterized by loss of striatal neurons. This is thought to be caused by an expanded, unstable trinucleotide repeat in the huntingtin gene, which translates as a polyglutamine repeat in the protein product. A fairly broad range in the number of trinucleotide repeats has been identified in normal controls, and repeat numbers in excess of 40 have been described as pathological. The huntingtin locus is large, spanning 180 kb and consisting of 67 exons. The huntingtin gene is widely expressed and is required for normal development. It is expressed as 2 alternatively polyadenylated forms displaying different relative abundance in various fetal and adult tissues. The larger transcript is approximately 13.7 kb and is expressed predominantly in adult and fetal brain whereas the smaller transcript of approximately 10.3 kb is more widely expressed. The genetic defect leading to Huntington's disease may not necessarily eliminate transcription, but may confer a new property on the mRNA or alter the function of the protein. One candidate is the huntingtin-associated protein-1, highly expressed in brain, which has increased affinity for huntingtin protein with expanded polyglutamine repeats. This gene contains an upstream open reading frame in the 5' UTR that inhibits expression of the huntingtin gene product through translational repression. [provided by RefSeq, Jul 2008]

GeneCards Summary for HTT Gene

HTT (Huntingtin) is a Protein Coding gene. Diseases associated with HTT include Huntington Disease and Juvenile Huntington Disease. Among its related pathways are fMLP Pathway and EGFR1 Signaling Pathway. GO annotations related to this gene include identical protein binding and transcription factor binding.

UniProtKB/Swiss-Prot for HTT Gene

  • May play a role in microtubule-mediated transport or vesicle function.

Gene Wiki entry for HTT Gene

No data available for Tocris Summary , PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for HTT Gene

Genomics for HTT Gene

Regulatory Elements for HTT Gene

Enhancers for HTT Gene
GeneHancer Identifier Score Enhancer Sources TSS distance (kb) Number of Genes Away Size (kb) Transcription Factor Binding Sites within enhancer Other Gene Targets for Enhancer

Enhancers around HTT on UCSC Golden Path with GeneCards custom track

Promoters for HTT Gene
Ensembl Regulatory Elements (ENSRs) TSS Distance (bp) Size (bp) Binding Sites for Transcription Factors within promoters

ENSRs around HTT on UCSC Golden Path with GeneCards custom track

Genomic Location for HTT Gene

3,074,510 bp from pter
3,243,960 bp from pter
169,451 bases
Plus strand

Genomic View for HTT Gene

Genes around HTT on UCSC Golden Path with GeneCards custom track

Cytogenetic band:
HTT Gene in genomic location: bands according to Ensembl, locations according to GeneLoc (and/or Entrez Gene and/or Ensembl if different)
Genomic Location for HTT Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

RefSeq DNA sequence for HTT Gene

Proteins for HTT Gene

  • Protein details for HTT Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Protein Accession:
    Secondary Accessions:
    • Q9UQB7

    Protein attributes for HTT Gene

    3142 amino acids
    Molecular mass:
    347603 Da
    Quaternary structure:
    • Binds SH3GLB1 (By similarity). Interacts through its N-terminus with PRPF40A. Interacts with PQBP1, SETD2 and SYVN. Interacts with PFN1. Interacts with TPR; the interaction is inhibited by forms of Huntingtin with expanded polyglutamine stretch.

    Three dimensional structures from OCA and Proteopedia for HTT Gene

neXtProt entry for HTT Gene

Proteomics data for HTT Gene at MOPED

Post-translational modifications for HTT Gene

  • Cleaved by apopain downstream of the polyglutamine stretch. The resulting N-terminal fragment is cytotoxic and provokes apoptosis.
  • Forms with expanded polyglutamine expansion are specifically ubiquitinated by SYVN1, which promotes their proteasomal degradation.
  • Phosphorylation at Ser-1179 and Ser-1199 by CDK5 in response to DNA damage in nuclei of neurons protects neurons against polyglutamine expansion as well as DNA damage mediated toxicity.
  • Ubiquitination at Lys 1262, Lys 1402, Lys 1431, and Lys 2417
  • Modification sites at PhosphoSitePlus

Other Protein References for HTT Gene

ENSEMBL proteins:
REFSEQ proteins:

Antibody Products

  • Cell Signaling Technology (CST) Antibodies for HTT (Huntingtin)

No data available for DME Specific Peptides for HTT Gene

Domains & Families for HTT Gene

Gene Families for HTT Gene

Protein Domains for HTT Gene

Suggested Antigen Peptide Sequences for HTT Gene

Graphical View of Domain Structure for InterPro Entry



  • The N-terminal Gln-rich and Pro-rich domain has great conformational flexibility and is likely to exist in a fluctuating equilibrium of alpha-helical, random coil, and extended conformations.
  • Belongs to the huntingtin family.
  • Contains 5 HEAT repeats.
  • The N-terminal Gln-rich and Pro-rich domain has great conformational flexibility and is likely to exist in a fluctuating equilibrium of alpha-helical, random coil, and extended conformations.
  • Belongs to the huntingtin family.
  • Contains 5 HEAT repeats.
genes like me logo Genes that share domains with HTT: view

Function for HTT Gene

Molecular function for HTT Gene

UniProtKB/Swiss-Prot Function:
May play a role in microtubule-mediated transport or vesicle function.

Gene Ontology (GO) - Molecular Function for HTT Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0044325 ion channel binding IDA 12873381
genes like me logo Genes that share ontologies with HTT: view
genes like me logo Genes that share phenotypes with HTT: view

Human Phenotype Ontology for HTT Gene

HPO Id HPO Name Alternative Ids Definition Synonyms

Animal Models for HTT Gene

MGI Knock Outs for HTT:

Animal Model Products

No data available for Enzyme Numbers (IUBMB) , Transcription Factor Targets and HOMER Transcription for HTT Gene

Localization for HTT Gene

Subcellular locations from UniProtKB/Swiss-Prot for HTT Gene

Cytoplasm. Nucleus. Note=The mutant Huntingtin protein colocalizes with AKAP8L in the nuclear matrix of Huntington disease neurons. Shuttles between cytoplasm and nucleus in a Ran GTPase-independent manner.

Subcellular locations from

Jensen Localization Image for HTT Gene COMPARTMENTS Subcellular localization image for HTT gene
Compartment Confidence
cytoskeleton 5
cytosol 5
endoplasmic reticulum 5
endosome 5
golgi apparatus 5
nucleus 5
vacuole 5
mitochondrion 4
plasma membrane 4
extracellular 2
lysosome 2

Gene Ontology (GO) - Cellular Components for HTT Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005770 late endosome IDA 17704510
GO:0005794 Golgi apparatus IDA 15837803
GO:0005829 cytosol IEA,IDA 20515468
GO:0030136 clathrin-coated vesicle IEA --
GO:0030425 dendrite IEA,IDA 7748555
genes like me logo Genes that share ontologies with HTT: view

Pathways & Interactions for HTT Gene

genes like me logo Genes that share pathways with HTT: view

Pathways by source for HTT Gene

2 Cell Signaling Technology pathways for HTT Gene
2 BioSystems pathways for HTT Gene
1 KEGG pathway for HTT Gene
2 Qiagen pathways for HTT Gene

SIGNOR curated interactions for HTT Gene

Is activated by:
Is inactivated by:
Other effect:

Gene Ontology (GO) - Biological Process for HTT Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0007030 Golgi organization IMP 20515468
GO:0007417 central nervous system development IEA --
GO:0034047 regulation of protein phosphatase type 2A activity IMP 21562226
GO:0045724 positive regulation of cilium assembly IMP 21985783
GO:0048513 animal organ development IBA --
genes like me logo Genes that share ontologies with HTT: view

Drugs & Compounds for HTT Gene

(28) Drugs for HTT Gene - From: Novoseek

Name Status Disease Links Group Role Mechanism of Action Clinical Trials

(25) Additional Compounds for HTT Gene - From: Novoseek

Name Synonyms Role CAS Number PubChem IDs PubMed IDs
genes like me logo Genes that share compounds with HTT: view

Transcripts for HTT Gene

Unigene Clusters for HTT Gene

Representative Sequences:

Alternative Splicing Database (ASD) splice patterns (SP) for HTT Gene

No ASD Table

Relevant External Links for HTT Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for HTT Gene

mRNA expression in normal human tissues for HTT Gene

Protein differential expression in normal tissues from HIPED for HTT Gene

This gene is overexpressed in Peripheral blood mononuclear cells (18.3).

Integrated Proteomics: protein expression in normal tissues and cell lines from ProteomicsDB, PaxDb, MOPED, and MaxQB for HTT Gene

SOURCE GeneReport for Unigene cluster for HTT Gene Hs.518450

mRNA Expression by UniProt/SwissProt for HTT Gene

Tissue specificity: Expressed in the brain cortex (at protein level). Widely expressed with the highest level of expression in the brain (nerve fibers, varicosities, and nerve endings). In the brain, the regions where it can be mainly found are the cerebellar cortex, the neocortex, the striatum, and the hippocampal formation.
genes like me logo Genes that share expression patterns with HTT: view

Protein tissue co-expression partners for HTT Gene

- Elite partner

Primer Products

No data available for mRNA expression in embryonic tissues and stem cells from LifeMap Discovery and mRNA differential expression in normal tissues for HTT Gene

Orthologs for HTT Gene

This gene was present in the common ancestor of animals.

Orthologs for HTT Gene

Organism Taxonomy Gene Similarity Type Details
(Bos Taurus)
Mammalia HTT 35
  • 84.14 (n)
  • 89.35 (a)
HTT 36
  • 89 (a)
(Canis familiaris)
Mammalia HTT 35
  • 87.27 (n)
  • 91.94 (a)
HD 36
  • 91 (a)
(Mus musculus)
Mammalia Htt 35
  • 86.38 (n)
  • 91.25 (a)
Htt 16
Htt 36
  • 91 (a)
(Pan troglodytes)
Mammalia HTT 35
  • 98.62 (n)
  • 98.66 (a)
HTT 36
  • 99 (a)
(Rattus norvegicus)
Mammalia Htt 35
  • 86.11 (n)
  • 91.28 (a)
(Monodelphis domestica)
Mammalia HTT 36
  • 86 (a)
(Ornithorhynchus anatinus)
Mammalia HTT 36
  • 83 (a)
(Gallus gallus)
Aves HTT 35
  • 75.5 (n)
  • 84.45 (a)
HTT 36
  • 84 (a)
(Anolis carolinensis)
Reptilia -- 36
  • 78 (a)
-- 36
  • 87 (a)
tropical clawed frog
(Silurana tropicalis)
Amphibia htt 35
  • 72.18 (n)
  • 76.94 (a)
(Danio rerio)
Actinopterygii hd 35
htt 35
  • 69.1 (n)
  • 73.77 (a)
htt 36
  • 72 (a)
fruit fly
(Drosophila melanogaster)
Insecta htt 36
  • 17 (a)
sea squirt
(Ciona savignyi)
Ascidiacea -- 36
  • 33 (a)
Species with no ortholog for HTT:
  • A. gosspyii yeast (Ashbya gossypii)
  • Actinobacteria (Mycobacterium tuberculosis)
  • African clawed frog (Xenopus laevis)
  • African malaria mosquito (Anopheles gambiae)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • baker's yeast (Saccharomyces cerevisiae)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • bread mold (Neurospora crassa)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • corn (Zea mays)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • fission yeast (Schizosaccharomyces pombe)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • K. lactis yeast (Kluyveromyces lactis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rainbow trout (Oncorhynchus mykiss)
  • rice (Oryza sativa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • thale cress (Arabidopsis thaliana)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • wheat (Triticum aestivum)
  • worm (Caenorhabditis elegans)

Evolution for HTT Gene

Gene Tree for HTT (if available)
Gene Tree for HTT (if available)

Paralogs for HTT Gene

(1) SIMAP similar genes for HTT Gene using alignment to 2 proteins:

genes like me logo Genes that share paralogs with HTT: view

No data available for Paralogs for HTT Gene

Variants for HTT Gene

Polymorphic Variants from UniProtKB/Swiss-Prot for HTT Gene

The poly-Gln region of HTT is highly polymorphic (10 to 35 repeats) in the normal population and is expanded to about 36-120 repeats in Huntington disease patients. The repeat length usually increases in successive generations, but contracts also on occasion. The adjacent poly-Pro region is also polymorphic and varies between 7-12 residues. Polyglutamine expansion leads to elevated susceptibility to apopain cleavage and likely result in accelerated neuronal apoptosis (PubMed:8696339).

Sequence variations from dbSNP and Humsavar for HTT Gene

SNP ID Clin Chr 04 pos Sequence Context AA Info Type
rs3025837 -, - 3,173,118(-) GTCGT(C/G/T)CTCCT reference, missense
rs363075 - 3,135,947(-) AGCCC(C/T)TCTGT reference, missense
rs35892913 - 3,146,843(-) CCCAA(C/T)GGTAC reference, missense
rs1143646 - 3,146,926(+) TTGAT(G/T)TTGGC reference, missense
rs3025843 - 3,154,311(-) GTTTG(C/T)TAGAG reference, missense

Structural Variations from Database of Genomic Variants (DGV) for HTT Gene

Variant ID Type Subtype PubMed ID
nsv461163 CNV Gain 19166990
esv2667257 CNV Deletion 23128226
esv8475 CNV Loss 19470904
nsv461164 CNV Loss 19166990
nsv524211 CNV Loss 19592680
nsv470003 CNV Loss 18288195
dgv5428n71 CNV Loss 21882294
nsv878455 CNV Loss 21882294
nsv878456 CNV Loss 21882294
esv2726869 CNV Deletion 23290073
esv2726870 CNV Deletion 23290073
nsv878457 CNV Loss 21882294

Variation tolerance for HTT Gene

Residual Variation Intolerance Score: 0.145% of all genes are more intolerant (likely to be disease-causing)
Gene Damage Index Score: 22.05; 99.38% of all genes are more intolerant (likely to be disease-causing)

Relevant External Links for HTT Gene

Human Gene Mutation Database (HGMD)

Disorders for HTT Gene

MalaCards: The human disease database

(19) MalaCards diseases for HTT Gene - From: OMIM, ClinVar, GeneTests, Orphanet, DISEASES, Novoseek, and GeneCards

Disorder Aliases PubMed IDs
huntington disease
  • congenital anomalies of kidney and urinary tract 2
juvenile huntington disease
  • huntington disease, juvenile onset
obsessive-compulsive disorder
  • obsessive-compulsive disorder, protection against
choreatic disease
  • chorea
spinal and bulbar muscular atrophy of kennedy
  • kennedy's disease
- elite association - COSMIC cancer census association via MalaCards
Search HTT in MalaCards View complete list of genes associated with diseases


  • Huntington disease (HD) [MIM:143100]: A neurodegenerative disorder characterized by involuntary movements (chorea), general motor impairment, psychiatric disorders and dementia. Onset of the disease occurs usually in the third or fourth decade of life. Onset and clinical course depend on the degree of poly-Gln repeat expansion, longer expansions resulting in earlier onset and more severe clinical manifestations. Neuropathology of Huntington disease displays a distinctive pattern with loss of neurons, especially in the caudate and putamen. Note=The disease is caused by mutations affecting the gene represented in this entry.

Relevant External Links for HTT

Genetic Association Database (GAD)
Human Genome Epidemiology (HuGE) Navigator
Atlas of Genetics and Cytogenetics in Oncology and Haematology:
genes like me logo Genes that share disorders with HTT: view

No data available for Genatlas for HTT Gene

Publications for HTT Gene

  1. A novel gene containing a trinucleotide repeat that is expanded and unstable on Huntington's disease chromosomes. (PMID: 8458085) Macdonald M. … Harper P.S. (Cell 1993) 2 3 4 23 67
  2. Huntingtin facilitates polycomb repressive complex 2. (PMID: 19933700) Seong I.S. … MacDonald M.E. (Hum. Mol. Genet. 2010) 3 23
  3. Evaluation of IP-RP-HPLC for length determination of the trinucleotide repeat fragments in Huntington's disease. (PMID: 20056037) Skrzypczak M. … Froster U.G. (J Chromatogr Sci 2010) 3 23
  4. Full-length huntingtin levels modulate body weight by influencing insulin-like growth factor 1 expression. (PMID: 20097678) Pouladi M.A. … Hayden M.R. (Hum. Mol. Genet. 2010) 3 23
  5. Huntingtin interacts with the cue domain of gp78 and inhibits gp78 binding to ubiquitin and p97/VCP. (PMID: 20126661) Yang H. … Fang S. (PLoS ONE 2010) 3 23

Products for HTT Gene

Sources for HTT Gene