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Protein MUTYH PDB 1x51.png
Available structures
PDBOrtholog search: PDBe RCSB
AliasesMUTYH, MYH, mutY DNA glycosylase, mutY homolog (E. coli)
External IDsOMIM: 604933 MGI: 1917853 HomoloGene: 8156 GeneCards: MUTYH
RefSeq (mRNA)


RefSeq (protein)


Location (UCSC)Chr 1: 45.33 – 45.34 MbChr 4: 116.81 – 116.82 Mb
PubMed search[3][4]
View/Edit HumanView/Edit Mouse

MUTYH (mutY DNA glycosylase) is a human gene that encodes a DNA glycosylase, MUTYH glycosylase. It is involved in oxidative DNA damage repair and is part of the base excision repair pathway. The enzyme excises adenine bases from the DNA backbone at sites where adenine is inappropriately paired with guanine, cytosine, or 8-oxo-7,8-dihydroguanine, a common form of oxidative DNA damage.

The protein is localized to the nucleus and mitochondria. Mutations in this gene result in heritable predisposition to colon and stomach cancer. Multiple transcript variants encoding different isoforms have been found for this gene.[5]

Location and structure[edit]

MUTYH has its locus on the short (p) arm of chromosome 1 (1p34.1), from base pair 45,464,007 to base pair 45,475,152 (45,794,835–45,806,142). The gene is composed of 16 exons and has a size of 546 amino acids[6] and is approximately 7.1kb.[7] The presence of disulfide crosslinking gives rise to a complex crystal structure of the MUTY-DNA.[8] The protein structure of the MUTYH gene has its N-terminal on the 5’ and the C-terminal on the 3’. Within the N-terminal. There is an helix-hairpin-helix and pseudo helix-hairpin-helix contained within the N-terminal, in addition to an iron cluster motif


Repair of oxidative DNA damage is the result of a collaborative effort of MUTYH, OGG1, and MTH1. MUTYH gene acts on the adenine base that have an A to 8-oxoG pairing while OGG1 (on chromosome 3 (3p26.2) part of the base excision repair pathway) detects and acts on 8-oxoG, thereby removing it.[9][10] The resultant effect of the action of the genes results in correction of transversion mutations made by the incorrect G:C, T:A pairing. TP53 transcriptionally regulates MUTYH and it can be surmised that it may potentially act as a regulator for p53.[11]


MUTYH is overexpressed in CD4-T cells, the prostate, the colon and the rectum. There is evidence of MUTYH expression in kidney, intestinal, nervous system and muscle tissues.[6]

Protein interactions[edit]

MUTYH has been shown to interact with Replication protein A1,[12] PCNA[12] and APEX1.[12]

The excision of the bases causes the formation of an apurinic/ apyrimidinic (AP site) gap. These gap sites are mutagenic in nature and require constant and immediate emendation and this is achieved by the active involvement of protein complexes that repair the AP gap site via short and long patch repair pathways. The short patch repair pathway employs POLB (DNA polymerase beta), APE1, XRCC1, PARP1 with the addition of either the LIG1 or LIG3 genes. When an insertion of one nucleotide occurs, the enzyme AP endonuclease (APEX/APE1) cuts out the mismatched base pairs at the AP site and this causes the evolvement of 5’dRP (5’ deoxyribose phosphate), a terminal blocking group, and 3’-OH ( 3’ hydroxyl end). POLB is required to remove the 5’dRP, and it does this by enzymatic activity, namely polymerase and dRP lyase. DNA ligase is used to seal the fragments after dRP excision causes the formation of 5’PO4 that is necessary to form the phosphodiester bonds of DNA. The purpose of PARP1 and XRCC1 in the single strand break repair pathway, is to stabilize the strands of DNA while they undergo repair, synthesis, gap-filling and ligation. PARP1 acts as a recruit agent for XRCC1. The nick sealing of the strands is accomplished by the formation of LIG1 (DNA ligase 1) and/or LIG3/ XRCCI complex that attach to processed end of the corrected strands and reinstate the original conformation of the strand. Long patch repair comes into play when more nucleotides are involved, ranging from 2 to 12. It is hypothesized that Polymerase 𝜹 (POLD) and Polymerase 𝛆 (POLE), assisted by the PCNA (proliferating cell nuclear antigen) in conjunction with replication factor C (RFC) that acts as a stabilizer and places newly synthesized nucleotides on the DNA strand. Both the polymerases repair the DNA by employing the strand displacement synthesis mechanism. This mechanism occurs downstream a DNA strand and the 5’ is transformed into a “flap intermediate” causing it to be “displaced”. FEN1 (flap structure-specific endonuclease 1), a nuclease, removes the displaced strand and this results in a ligatable strand of DNA.Long patch repair, like short patch repair, includes the use of APE1 and PARP1 and LIG1. The repair pathway is partially determined by the amount of ATP present after the removal of the deoxyribose phosphate end. The long patch repair pathway is preferred under conditions of low ATP concentration while the short repair pathway is preferred under high concentrations of ATP.[13]

Other notable interactions include MUTYH and Replication protein A is a single strand binding protein that prevents the annealing of DNA during replication, it also plays a role as an activator for damage repair on DNA. There is a hypothetical relation between the interaction of Mismatch Repair proteins (MMR) such as MSH 2,3 and 6, MLH1, PMS1 and 2, and MUTYH in which the proposed result of their partnering is to increase susceptibility to cancer.[14]

Chemical interactions[edit]

The gene interacts with the following chemicals:

a) Carbon tetrachloride: decreased expression of MUTYH mRNA

b) Ethanol: When treated together with dronabinol) increased expression of MUTYH mRNA. When used alone, it has conflicting results of decreased and increased the MUTYH mRNA.

c) Ethinylestradiol: When used alone it results in the increased expression of MUTYH mRNA.When treated together with tetrachlorodibenzo p dioxin, there is increased expression of MUTYH mRNA.

d) Tamoxifen: affects MUTYH[15]

Related conditions[edit]

The table of the Gene-phenotype associations summarizes the diseases/conditions that arise from mutations in MUTYH

Phenotype/Condition Mode of Inheritance
Familial adenomatous polyposis Autosomal recessive[16]
Pilomatricoma Somatic mutation[17]
Gastric cancer Somatic mutation[18]
Endometrial cancer Biallelic germline mutation[19]

Mutations in the MUTYH gene cause an autosomal recessive disorder similar to familial adenomatous polyposis (also called MUTYH-associated polyposis). Polyps caused by mutated MUTYH do not appear until adulthood and are less numerous than those found in patients with APC gene mutations. Both copies of the MUTYH gene are mutated in individuals who have autosomal recessive familial adenomatous polyposis i.e., the mutations for the MUTYH gene is biallelic. Mutations in this gene affect the ability of cells to correct mistakes made during DNA replication. Most reported mutations in this gene cause production of a nonfunctional or low functioning glycosylase enzyme. When base excision repair in the cell is compromised, mutations in other genes build up, leading to cell overgrowth and possibly tumor formation. The two most common mutations in Caucasian Europeans are exchanges of amino acids (the building blocks of proteins) in the enzyme. One mutation replaces the amino acid tyrosine with cysteine at position 179 (also written as p.Tyr179Cys (p.Y179C) or, when describing the nucleotide change, written as c.536A>G). The other common mutation switches the amino acid glycine with aspartic acid at position 396 (also written as p.Gly396Asp(G396D) or c.1187G>A).[20]

The association of the gene with gastric cancer is somewhat indirect and multifactorial. When a subject is infected with Helicobacter pylori (H. pylori), the bacteria cause the formation of free oxygen radicals that are present in the gastric mucosa and this increases the propensity of the genes to incur oxidative damage . A study of 95 cases of patients who had sporadic cancers, initiated by the presence of H. pylori, and two of the 95 patients had biallelic mutation of the MUTYH gene. The somatic missense mutations for the first identified cancer occurred at codon 391, in which there was a change in the nucleotide bases from CCG (codon for amino acid proline) to TCG (codon for amino acid serine), while the second cancer had a nucleotide base change at codon 400 from CAG (codon for amino acid glutamine) to GGG (codon for amino acid arginine). The mutations were found to be highly conserved in the Nudix hydrolase domain of MUTYH. These amino acid mutations provide the basis for the somatic mutations in the gastric system.[21]

Pilomatricoma has been noted in a case that concerned two siblings who were the offspring of consanguineous parents. The siblings had a 2 base pair homozygous insertion on the MUTYH gene ( exon 13). Consequently, a frameshift occurred due to the insertion and a premature stop codon was read at 438 on the gene. Pilomatricoma was the phenotypic manifestation of this mutation. One of the siblings was also found to have rectal adenocarcinoma. It is worthy to note that CTNNB1, a gene associated with pilomatricoma, was also investigated. However, no mutations in this gene were found, thereby dismissing it as a possible cause for this case.[22]

There is an established correlation between aging and the elevation 8-oxoG concentrations, particularly in organs that exhibit reduced cell proliferation such as the kidneys, liver, brain and lungs.[23] Presence of 8-oxoG also occurs in large concentrations in patients with neurological conditions such as Alzheimer's, Parkinson's and Huntington's disease.[24] MUTYH causes immoderate formation of single stranded breaks via base excision repair, under acute oxidative stress conditions.[25][26] When the 8-oxoguanine species accumulate and increase in concentration in the neurons, MUTYH responds by triggering their degeneration.[27]


  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000132781 - Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000028687 - Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ "Entrez Gene: MUTYH mutY homolog (E. coli)".
  6. ^ a b GeneCard for MUTYH
  7. ^ Slupska MM, Baikalov C, Luther WM, Chiang JH, Wei YF, Miller JH (July 1996). "Cloning and sequencing a human homolog (hMYH) of the Escherichia coli mutY gene whose function is required for the repair of oxidative DNA damage". Journal of Bacteriology. 178 (13): 3885–92. doi:10.1128/jb.178.13.3885-3892.1996. PMC 232650. PMID 8682794.
  8. ^ Online Mendelian Inheritance in Man (OMIM): MUTYH - 604933
  9. ^ Shinmura K, Yokota J (August 2001). "The OGG1 gene encodes a repair enzyme for oxidatively damaged DNA and is involved in human carcinogenesis". Antioxidants & Redox Signaling. 3 (4): 597–609. doi:10.1089/15230860152542952. PMID 11554447.
  10. ^ Kitsera N, Stathis D, Lühnsdorf B, Müller H, Carell T, Epe B, Khobta A (August 2011). "8-Oxo-7,8-dihydroguanine in DNA does not constitute a barrier to transcription, but is converted into transcription-blocking damage by OGG1". Nucleic Acids Research. 39 (14): 5926–34. doi:10.1093/nar/gkr163. PMC 3152326. PMID 21441539.
  11. ^ Oka S, Leon J, Tsuchimoto D, Sakumi K, Nakabeppu Y (February 2015). "MUTYH, an adenine DNA glycosylase, mediates p53 tumor suppression via PARP-dependent cell death". Oncogenesis. 4 (2): e142. doi:10.1038/oncsis.2015.4. PMC 4338427. PMID 25706342.
  12. ^ a b c Parker A, Gu Y, Mahoney W, Lee SH, Singh KK, Lu AL (February 2001). "Human homolog of the MutY repair protein (hMYH) physically interacts with proteins involved in long patch DNA base excision repair". The Journal of Biological Chemistry. 276 (8): 5547–55. doi:10.1074/jbc.M008463200. PMID 11092888.
  13. ^ Kim YJ, Wilson DM (January 2012). "Overview of base excision repair biochemistry". Current Molecular Pharmacology. 5 (1): 3–13. doi:10.2174/1874467211205010003. PMC 3459583. PMID 22122461.
  14. ^ Niessen RC, Sijmons RH, Ou J, Olthof SG, Osinga J, Ligtenberg MJ, Hogervorst FB, Weiss MM, Tops CM, Hes FJ, de Bock GH, Buys CH, Kleibeuker JH, Hofstra RM (March 2006). "MUTYH and the mismatch repair system: partners in crime?" (PDF). Human Genetics. 119 (1–2): 206–11. doi:10.1007/s00439-005-0118-5. PMID 16408224. S2CID 22651739.
  15. ^ "MUTYH". Entrez Gene.
  16. ^ Online Mendelian Inheritance in Man (OMIM): Familial adenomatous polyposis 2; FAP2 - 608456
  17. ^ Online Mendelian Inheritance in Man (OMIM): Pilomatricoma - 132600
  18. ^ Online Mendelian Inheritance in Man (OMIM): Gastric Cancer - 613659
  19. ^ Tricarico R, Bet P, Ciambotti B, Di Gregorio C, Gatteschi B, Gismondi V, Toschi B, Tonelli F, Varesco L, Genuardi M (February 2009). "Endometrial cancer and somatic G>T KRAS transversion in patients with constitutional MUTYH biallelic mutations". Cancer Letters. 274 (2): 266–70. doi:10.1016/j.canlet.2008.09.022. PMID 18980800.
  20. ^ Aretz S, Tricarico R, Papi L, Spier I, Pin E, Horpaopan S, Cordisco EL, Pedroni M, Stienen D, Gentile A, Panza A, Piepoli A, de Leon MP, Friedl W, Viel A, Genuardi M (July 2014). "MUTYH-associated polyposis (MAP): evidence for the origin of the common European mutations p.Tyr179Cys and p.Gly396Asp by founder events". European Journal of Human Genetics. 22 (7): 923–9. doi:10.1038/ejhg.2012.309. PMC 4060104. PMID 23361220.
  21. ^ Kim CJ, Cho YG, Park CH, Kim SY, Nam SW, Lee SH, Yoo NJ, Lee JY, Park WS (September 2004). "Genetic alterations of the MYH gene in gastric cancer". Oncogene. 23 (40): 6820–2. doi:10.1038/sj.onc.1207574. PMID 15273732.
  22. ^ Baglioni S, Melean G, Gensini F, Santucci M, Scatizzi M, Papi L, Genuardi M (April 2005). "A kindred with MYH-associated polyposis and pilomatricomas". American Journal of Medical Genetics. Part A. 134A (2): 212–4. doi:10.1002/ajmg.a.30585. PMID 15690400. S2CID 21866377.
  23. ^ Møller P, Løhr M, Folkmann JK, Mikkelsen L, Loft S (May 2010). "Aging and oxidatively damaged nuclear DNA in animal organs". Free Radical Biology & Medicine. 48 (10): 1275–85. doi:10.1016/j.freeradbiomed.2010.02.003. PMID 20149865.
  24. ^ Bjørge MD, Hildrestrand GA, Scheffler K, Suganthan R, Rolseth V, Kuśnierczyk A, Rowe AD, Vågbø CB, Vetlesen S, Eide L, Slupphaug G, Nakabeppu Y, Bredy TW, Klungland A, Bjørås M (December 2015). "Synergistic Actions of Ogg1 and Mutyh DNA Glycosylases Modulate Anxiety-like Behavior in Mice" (PDF). Cell Reports. 13 (12): 2671–8. doi:10.1016/j.celrep.2015.12.001. PMID 26711335.
  25. ^ Oka S, Ohno M, Tsuchimoto D, Sakumi K, Furuichi M, Nakabeppu Y (2008). "Two distinct pathways of cell death triggered by oxidative damage to nuclear and mitochondrial DNAs". The EMBO Journal. 27 (2): 421–32. doi:10.1038/sj.emboj.7601975. PMC 2234344. PMID 18188152.
  26. ^ Oka S, Nakabeppu Y (2011). "DNA glycosylase encoded by MUTYH functions as a molecular switch for programmed cell death under oxidative stress to suppress tumorigenesis". Cancer Science. 102 (4): 677–82. doi:10.1111/j.1349-7006.2011.01869.x. PMID 21235684.
  27. ^ Sheng Z, Oka S, Tsuchimoto D, Abolhassani N, Nomaru H, Sakumi K, Yamada H, Nakabeppu Y (2012). "8-Oxoguanine causes neurodegeneration during MUTYH-mediated DNA base excision repair". The Journal of Clinical Investigation. 122 (12): 4344–61. doi:10.1172/JCI65053. PMC 3533558. PMID 23143307.

Further reading[edit]

External links[edit]