Harmonizome 3.0

hydroxyacid oxidase (glycolate oxidase) 1

This gene is one of three related genes that have 2-hydroxyacid oxidase activity yet differ in encoded protein amino acid sequence, tissue expression and substrate preference. Subcellular location of the encoded protein is the peroxisome. Specifically, this gene is expressed primarily in liver and pancreas and the encoded protein is most active on glycolate, a two-carbon substrate. The protein is also active on 2-hydroxy fatty acids. The transcript detected at high levels in pancreas may represent an alternatively spliced form or the use of a multiple near-consensus upstream polyadenylation site. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit IV isoform 1 pseudogene 1

cytochrome c oxidase subunit IV isoform 1 pseudogene 2

cytochrome c oxidase subunit VIIc pseudogene

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 7

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 5

cytochrome c oxidase subunit Va

Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. The mitochondrially-encoded subunits perform the electron transfer of proton pumping activities. The functions of the nuclear-encoded subunits are unknown but they may play a role in the regulation and assembly of the complex. This gene encodes the nuclear-encoded subunit Va of the human mitochondrial respiratory chain enzyme. A pseudogene COX5AP1 has been found in chromosome 14q22. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit Vb

Cytochrome C oxidase (COX) is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. The mitochondrially-encoded subunits perform the electron transfer and proton pumping activities. The functions of the nuclear-encoded subunits are unknown but they may play a role in the regulation and assembly of the complex. This gene encodes the nuclear-encoded subunit Vb of the human mitochondrial respiratory chain enzyme. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit VIIa polypeptide 2 like

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes a protein similar to polypeptides 1 and 2 of subunit VIIa in the C-terminal region, and also highly similar to the mouse Sig81 protein sequence. This gene is expressed in all tissues, and upregulated in a breast cancer cell line after estrogen treatment. It is possible that this gene represents a regulatory subunit of COX and mediates the higher level of energy production in target cells by estrogen. Several transcript variants, some protein-coding and others non-protein coding, have been found for this gene. [provided by RefSeq, Jan 2016]

cytochrome c oxidase assembly factor 1 homolog (S. cerevisiae) pseudogene

SCO1 cytochrome c oxidase assembly protein

Mammalian cytochrome c oxidase (COX) catalyzes the transfer of reducing equivalents from cytochrome c to molecular oxygen and pumps protons across the inner mitochondrial membrane. In yeast, 2 related COX assembly genes, SCO1 and SCO2 (synthesis of cytochrome c oxidase), enable subunits 1 and 2 to be incorporated into the holoprotein. This gene is the human homolog to the yeast SCO1 gene. [provided by RefSeq, Jul 2008]

mitochondrially encoded cytochrome c oxidase I pseudogene

cytochrome c oxidase subunit VIc pseudogene 4

translational activator of mitochondrially encoded cytochrome c oxidase I

This gene encodes a mitochondrial protein that function as a translational activator of mitochondrially-encoded cytochrome c oxidase 1. Mutations in this gene are associated with Leigh syndrome.[provided by RefSeq, Mar 2010]

cytochrome c oxidase subunit VIIb2

Predicted to be involved in mitochondrial electron transport, cytochrome c to oxygen. Predicted to act upstream of or within spermatogenesis. Located in mitochondrion. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit VIc

Cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes subunit VIc, which has 77% amino acid sequence identity with mouse subunit VIc. This gene is up-regulated in prostate cancer cells. A pseudogene has been found on chromosomes 16p12. [provided by RefSeq, Jul 2010]

cytochrome c oxidase subunit VIa polypeptide 1

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in the electron transfer and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes polypeptide 1 (liver isoform) of subunit VIa, and polypeptide 1 is found in all non-muscle tissues. Polypeptide 2 (heart/muscle isoform) of subunit VIa is encoded by a different gene, and is present only in striated muscles. These two polypeptides share 66% amino acid sequence identity. It has been reported that there may be several pseudogenes on chromosomes 1, 6, 7q21, 7q31-32 and 12. However, only one pseudogene (COX6A1P) on chromosome 1p31.1 has been documented. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit VIa polypeptide 2

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes polypeptide 2 (heart/muscle isoform) of subunit VIa, and polypeptide 2 is present only in striated muscles. Polypeptide 1 (liver isoform) of subunit VIa is encoded by a different gene, and is found in all non-muscle tissues. These two polypeptides share 66% amino acid sequence identity. [provided by RefSeq, Jul 2008]

oxidase (cytochrome c) assembly 1-like

This gene encodes an evolutionarily conserved protein that is localized to the inner mitochondrial membrane. The encoded protein is essential for the translocation of the N-terminal tail of subunit 2 of cytochrome c oxidase, and is involved in the assembly of the cytochrome c oxidase and ATPase complexes of the mitochondrial respiratory chain. [provided by RefSeq, Jul 2016]

COX19 cytochrome c oxidase assembly factor

COX19 encodes a cytochrome c oxidase (COX)-assembly protein. The S. cerevisiae Cox19 protein may play a role in metal transport to the mitochondrial intermembrane space and assembly of complex IV of the mitochondrial respiratory chain (Sacconi et al., 2005 [PubMed 16212937]).[supplied by OMIM, Mar 2008]

cytochrome c oxidase subunit Vb pseudogene 8

cytochrome c oxidase subunit Vb pseudogene 4

cytochrome c oxidase subunit Vb pseudogene 5

cytochrome c oxidase subunit Vb pseudogene 6

cytochrome c oxidase subunit Vb pseudogene 7

cytochrome c oxidase subunit Vb pseudogene 1

cytochrome c oxidase subunit Vb pseudogene 2

cytochrome c oxidase subunit Vb pseudogene 3

cytochrome c oxidase subunit VIIb pseudogene

COX17 cytochrome c oxidase copper chaperone pseudogene 1

COX20 cytochrome c oxidase assembly factor pseudogene 2

COX20 cytochrome c oxidase assembly factor pseudogene 1

SCO1 cytochrome c oxidase assembly protein pseudogene

COX14 cytochrome c oxidase assembly factor

This gene encodes a small single-pass transmembrane protein that localizes to mitochondria. This protein may play a role in coordinating the early steps of cytochrome c oxidase (COX; also known as complex IV) subunit assembly and, in particular, the synthesis and assembly of the COX I subunit of the holoenzyme. Mutations in this gene have been associated with mitochondrial complex IV deficiency. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2012]

cytochrome c oxidase subunit VIIb pseudogene 2

cytochrome c oxidase subunit VIIb pseudogene 1

cytochrome c oxidase subunit VIIa polypeptide 2 (liver) pseudogene 2

Predicted to be involved in mitochondrial respirasome assembly and regulation of oxidative phosphorylation. Predicted to be located in mitochondrial inner membrane. Predicted to be part of respiratory chain complex. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit VIIa polypeptide 2 like pseudogene

cytochrome c oxidase subunit VIIb pseudogene

cytochrome c oxidase subunit VIc pseudogene 5

cytochrome c oxidase subunit VIc pseudogene 6

COX18 cytochrome c oxidase assembly factor

This gene encodes a cytochrome c oxidase assembly protein. The encoded protein is essential for integral membrane protein insertion into the mitochondrial inner membrane. It is also required for cytochrome c oxidase assembly and activity. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

COX10 heme A:farnesyltransferase cytochrome c oxidase assembly factor

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes heme A:farnesyltransferase, which is not a structural subunit but required for the expression of functional COX and functions in the maturation of the heme A prosthetic group of COX. This protein is predicted to contain 7-9 transmembrane domains localized in the mitochondrial inner membrane. A gene mutation, which results in the substitution of a lysine for an asparagine (N204K), is identified to be responsible for cytochrome c oxidase deficiency. In addition, this gene is disrupted in patients with CMT1A (Charcot-Marie-Tooth type 1A) duplication and with HNPP (hereditary neuropathy with liability to pressure palsies) deletion. [provided by RefSeq, Jul 2008]

COX11 cytochrome c oxidase copper chaperone

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes a protein which is not a structural subunit, but may be a heme A biosynthetic enzyme involved in COX formation, according to the yeast mutant studies. However, the studies in Rhodobacter sphaeroides suggest that this gene is not required for heme A biosynthesis, but required for stable formation of the Cu(B) and magnesium centers of COX. This human protein is predicted to contain a transmembrane domain localized in the mitochondrial inner membrane. Multiple transcript variants encoding different isoforms have been found for this gene. A related pseudogene has been found on chromosome 6. [provided by RefSeq, Jun 2009]

cytochrome c oxidase assembly homolog 15 (yeast)

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes a protein which is not a structural subunit, but may be essential for the biogenesis of COX formation and may function in the hydroxylation of heme O, according to the yeast mutant studies. This protein is predicted to contain 5 transmembrane domains localized in the mitochondrial inner membrane. Alternative splicing of this gene generates two transcript variants diverging in the 3' region. [provided by RefSeq, Jul 2008]

COX16 cytochrome c oxidase assembly homolog (S. cerevisiae)

Involved in mitochondrial cytochrome c oxidase assembly. Located in mitochondrial inner membrane. Implicated in mitochondrial complex IV deficiency nuclear type 22. [provided by Alliance of Genome Resources, Mar 2025]

COX17 cytochrome c oxidase copper chaperone

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes a protein which is not a structural subunit, but may be involved in the recruitment of copper to mitochondria for incorporation into the COX apoenzyme. This protein shares 92% amino acid sequence identity with mouse and rat Cox17 proteins. This gene is no longer considered to be a candidate gene for COX deficiency. A pseudogene COX17P has been found on chromosome 13. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit VIIc pseudogene 1

mitochondrially encoded cytochrome c oxidase II pseudogene

cytochrome c oxidase subunit VIa polypeptide 1 pseudogene 2

cytochrome c oxidase subunit VIa polypeptide 1 pseudogene 1

cytochrome c oxidase assembly factor 5

This gene encodes an ortholog of yeast Pet191, which in yeast is a subunit of a large oligomeric complex associated with the mitochondrial inner membrane, and required for the assembly of the cytochrome c oxidase complex. Mutations in this gene are associated with mitochondrial complex IV deficiency, a disorder of the mitochondrial respiratory chain with heterogeneous clinical manifestations, ranging from isolated myopathy to a severe disease affecting several tissues and organs. [provided by RefSeq, Dec 2011]

cytochrome c oxidase assembly factor 4 homolog (S. cerevisiae)

Predicted to be involved in mitochondrial cytochrome c oxidase assembly. Located in mitochondrion. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase assembly factor 7 (putative)

Involved in respiratory chain complex IV assembly. Located in mitochondrion and nucleoplasm. Is active in mitochondrial intermembrane space. Implicated in spinocerebellar ataxia with axonal neuropathy type 3. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase assembly factor 6

This gene encodes a member of the cytochrome c oxidase subunit 6B family. The encoded protein associates with cytochrome c oxidase may act has an cytochrome c oxidase mitochondrial respiratory complex VI assembly factor. Mutations in this gene may be associated with fatal infantile cardiomyopathy. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Sep 2014]

cytochrome c oxidase assembly factor 1 homolog (S. cerevisiae)

Involved in mitochondrial cytochrome c oxidase assembly and mitochondrial respiratory chain complex I assembly. Located in cytosol and mitochondrial inner membrane. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase assembly factor 3

This gene encodes a member of the cytochrome c oxidase assembly factor family. Studies of a related gene in fly suggest that the encoded protein is localized to mitochondria and is essential for cytochrome c oxidase function. [provided by RefSeq, Nov 2012]

cytochrome c oxidase subunit I

Contributes to cytochrome-c oxidase activity. Predicted to be involved in aerobic respiration; positive regulation of vasoconstriction; and respiratory electron transport chain. Located in mitochondrion. Part of mitochondrial membrane and respiratory chain complex IV. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit II

Contributes to cytochrome-c oxidase activity. Predicted to be involved in mitochondrial electron transport, cytochrome c to oxygen and positive regulation of vasoconstriction. Located in mitochondrial inner membrane. Part of mitochondrial membrane and respiratory chain complex IV. Biomarker of Huntington's disease and stomach cancer. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase III

Predicted to contribute to cytochrome-c oxidase activity. Involved in respiratory chain complex IV assembly. Located in mitochondrion. Part of mitochondrial membrane and respiratory chain complex IV. Implicated in MELAS syndrome. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit VIIa polypeptide 2 like pseudogene

cytochrome c oxidase subunit VIIIB, pseudogene

Cytochrome c oxidase is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. In addition a number of cytochrome c oxidase subunit pseudogenes have been found. This gene represents a subunit which has been inactivated by mutation and is nonfunctional in humans. [provided by RefSeq, Jul 2008]

COX20 cytochrome c oxidase assembly factor

This gene encodes a protein that plays a role in the assembly of cytochrome C oxidase, an important component of the respiratory pathway. It contains two transmembrane helices and localizes to the mitochondrial membrane. Mutations in this gene can cause mitochondrial complex IV deficiency, which results in ataxia and muscle hypotonia. There are multiple pseudogenes for this gene. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2015]

SCO2 cytochrome c oxidase assembly protein

Cytochrome c oxidase (COX) catalyzes the transfer of electrons from cytochrome c to molecular oxygen, which helps to maintain the proton gradient across the inner mitochondrial membrane that is necessary for aerobic ATP production. Human COX is a multimeric protein complex that requires several assembly factors; this gene encodes one of the COX assembly factors. The encoded protein is a metallochaperone that is involved in the biogenesis of cytochrome c oxidase subunit II. Mutations in this gene are associated with fatal infantile encephalocardiomyopathy and myopia 6. [provided by RefSeq, Oct 2014]

cytochrome c oxidase subunit VIc pseudogene 1

cytochrome c oxidase subunit VIc pseudogene 2

cytochrome c oxidase subunit VIc pseudogene 3

cytochrome c oxidase subunit IV isoform 2 (lung)

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes isoform 2 of subunit IV. Isoform 1 of subunit IV is encoded by a different gene, however, the two genes show a similar structural organization. Subunit IV is the largest nuclear encoded subunit which plays a pivotal role in COX regulation. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit IV isoform 1

Cytochrome c oxidase (COX) is the terminal enzyme of the mitochondrial respiratory chain. It is a multi-subunit enzyme complex that couples the transfer of electrons from cytochrome c to molecular oxygen and contributes to a proton electrochemical gradient across the inner mitochondrial membrane. The complex consists of 13 mitochondrial- and nuclear-encoded subunits. The mitochondrially-encoded subunits perform the electron transfer and proton pumping activities. The functions of the nuclear-encoded subunits are unknown but they may play a role in the regulation and assembly of the complex. This gene encodes the nuclear-encoded subunit IV isoform 1 of the human mitochondrial respiratory chain enzyme. It is located at the 3' of the NOC4 (neighbor of COX4) gene in a head-to-head orientation, and shares a promoter with it. Pseudogenes related to this gene are located on chromosomes 13 and 14. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2016]

COX11 cytochrome c oxidase copper chaperone pseudogene 1

cytochrome c oxidase subunit VIIa polypeptide 1 (muscle)

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes polypeptide 1 (muscle isoform) of subunit VIIa and the polypeptide 1 is present only in muscle tissues. Other polypeptides of subunit VIIa are present in both muscle and nonmuscle tissues, and are encoded by different genes. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit VIIa polypeptide 2 (liver)

Cytochrome c oxidase, the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of three catalytic subunits encoded by mitochondrial genes, and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, while the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes polypeptide 2 (liver isoform) of subunit VIIa, with this polypeptide being present in both muscle and non-muscle tissues. In addition to polypeptide 2, subunit VIIa includes polypeptide 1 (muscle isoform), which is present only in muscle tissues, and a related protein, which is present in all tissues. Alternative splicing results in multiple transcript variants. Related pseudogenes have been identified on chromosomes 4 and 14. [provided by RefSeq, Oct 2009]

cytochrome c oxidase subunit VIIb

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes subunit VIIb, which is highly similar to bovine COX VIIb protein and is found in all tissues. This gene may have several pseudogenes on chromosomes 1, 2, 20 and 22. [provided by RefSeq, Jun 2011]

cytochrome c oxidase subunit VIIc

Cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. This component is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may function in the regulation and assembly of the complex. This nuclear gene encodes subunit VIIc, which shares 87% and 85% amino acid sequence identity with mouse and bovine COX VIIc, respectively, and is found in all tissues. A pseudogene COX7CP1 has been found on chromosome 13. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous)

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes subunit VIb. Mutations in this gene are associated with severe infantile encephalomyopathy. Three pseudogenes COX6BP-1, COX6BP-2 and COX6BP-3 have been found on chromosomes 7, 17 and 22q13.1-13.2, respectively. [provided by RefSeq, Jan 2010]

cytochrome c oxidase subunit VIb polypeptide 2 (testis)

Predicted to be involved in oxidative phosphorylation. Located in mitochondrial crista. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit VIIa polypeptide 2 (liver) pseudogene 1

mitochondrially encoded cytochrome c oxidase III pseudogene

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 4

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 3

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 2

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 1

cytochrome c oxidase subunit VIb polypeptide 1 (ubiquitous) pseudogene 6

cytochrome c oxidase subunit VIIIC

Predicted to be involved in mitochondrial electron transport, cytochrome c to oxygen. Located in mitochondrion. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c oxidase subunit VIIIA (ubiquitous)

The protein encoded by this gene is the terminal enzyme of the respiratory chain, coupling the transfer of electrons from cytochrome c to molecular oxygen, with the concomitant production of a proton electrochemical gradient across the inner mitochondrial membrane. In addition to 3 mitochondrially encoded subunits, which perform the catalytic function, the eukaryotic enzyme contains nuclear-encoded smaller subunits, ranging in number from 4 in some organisms to 10 in mammals. It has been proposed that nuclear-encoded subunits may be involved in the modulation of the catalytic function. This gene encodes one of the nuclear-encoded subunits. [provided by RefSeq, Jul 2008]

cytochrome c oxidase subunit Va pseudogene 2

cytochrome c oxidase subunit Va pseudogene 1

cytochrome c oxidase subunit VIa polypeptide 1 pseudogene 3

cytochrome c oxidase assembly factor 8

This gene encodes a protein that localizes to the mitochondria, where it stimulates the release of cytochrome c, thereby promoting programmed cell death. Mutations in this gene have been found in individuals with mitochondrial complex IV deficiency. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2014]

cytochrome c oxidase associated subunit FA4

cytochrome c oxidase hypoxia associated subunit FA4L2

cytochrome c oxidase associated subunit FA4L3

cytochrome c oxidase subunit NDUFA4-like

proline dehydrogenase (oxidase) 1 pseudogene

urate oxidase, pseudogene

Urate oxidase is an enzyme that catalyzes the oxidation of uric acid to allantoin. This gene has been inactivated by mutation and is nonfunctional in humans and some other primates. [provided by RefSeq, Jul 2008]

amine oxidase, copper containing 2 (retina-specific)

Copper amine oxidases catalyze the oxidative conversion of amines to aldehydes and ammonia in the presence of copper and quinone cofactor. This gene shows high sequence similarity to copper amine oxidases from various species ranging from bacteria to mammals. The protein contains several conserved motifs including the active site of amine oxidases and the histidine residues that likely bind copper. It may be a critical modulator of signal transmission in retina, possibly by degrading the biogenic amines dopamine, histamine, and putrescine. This gene may be a candidate gene for hereditary ocular diseases. Alternate splicing results in multiple transcript variants. [provided by RefSeq, Jul 2008]

D-amino acid oxidase activator

This gene encodes a protein that may function as an activator of D-amino acid oxidase, which degrades the gliotransmitter D-serine, a potent activator of N-methyl-D-aspartate (NMDA) type glutamate receptors. Studies also suggest that one encoded isoform may play a role in mitochondrial function and dendritic arborization. Polymorphisms in this gene have been implicated in susceptibility to schizophrenia and bipolar affective disorder. Alternatively spliced transcript variants encoding different isoforms have been identified.[provided by RefSeq, Mar 2011]

monoamine oxidase B

The protein encoded by this gene belongs to the flavin monoamine oxidase family. It is a enzyme located in the mitochondrial outer membrane. It catalyzes the oxidative deamination of biogenic and xenobiotic amines and plays an important role in the metabolism of neuroactive and vasoactive amines in the central nervous sysytem and peripheral tissues. This protein preferentially degrades benzylamine and phenylethylamine. [provided by RefSeq, Jul 2008]

monoamine oxidase A

This gene is one of two neighboring gene family members that encode mitochondrial enzymes which catalyze the oxidative deamination of amines, such as dopamine, norepinephrine, and serotonin. Mutation of this gene results in Brunner syndrome. This gene has also been associated with a variety of other psychiatric disorders, including antisocial behavior. Alternatively spliced transcript variants encoding multiple isoforms have been observed. [provided by RefSeq, Jul 2012]

pyridoxamine 5'-phosphate oxidase

The enzyme encoded by this gene catalyzes the terminal, rate-limiting step in the synthesis of pyridoxal 5'-phosphate, also known as vitamin B6. Vitamin B6 is a required co-factor for enzymes involved in both homocysteine metabolism and synthesis of neurotransmitters such as catecholamine. Mutations in this gene result in pyridoxamine 5'-phosphate oxidase (PNPO) deficiency, a form of neonatal epileptic encephalopathy. [provided by RefSeq, Oct 2008]

dual oxidase 1

The protein encoded by this gene is a glycoprotein and a member of the NADPH oxidase family. The synthesis of thyroid hormone is catalyzed by a protein complex located at the apical membrane of thyroid follicular cells. This complex contains an iodide transporter, thyroperoxidase, and a peroxide generating system that includes proteins encoded by this gene and the similar DUOX2 gene. This protein is known as dual oxidase because it has both a peroxidase homology domain and a gp91phox domain. This protein generates hydrogen peroxide and thereby plays a role in the activity of thyroid peroxidase, lactoperoxidase, and in lactoperoxidase-mediated antimicrobial defense at mucosal surfaces. Two alternatively spliced transcript variants encoding the same protein have been described for this gene. [provided by RefSeq, Jul 2012]

dual oxidase 2

The protein encoded by this gene is a glycoprotein and a member of the NADPH oxidase family. The synthesis of thyroid hormone is catalyzed by a protein complex located at the apical membrane of thyroid follicular cells. This complex contains an iodide transporter, thyroperoxidase, and a peroxide generating system that includes this encoded protein and DUOX1. This protein is known as dual oxidase because it has both a peroxidase homology domain and a gp91phox domain. [provided by RefSeq, Jul 2008]

NADPH oxidase 1

This gene encodes a member of the NADPH oxidase family of enzymes responsible for the catalytic one-electron transfer of oxygen to generate superoxide or hydrogen peroxide. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Nov 2012]

NADPH oxidase 3

This gene encodes a member of the NOX family of NADPH oxidases. These enzymes have the capacity to generate superoxide and other reactive oxygen species (ROS) and transport electrons across the plasma membrane. The ROS generated by family members have been implicated in numerous biological functions including host defense, posttranlational processing of proteins, cellular signaling, regulation of gene expression, and cell differentiation. The protein encoded by this gene is expressed predominantly in the inner ear and is involved in the biogenesis of otoconia/otolith, which are crystalline structures of the inner ear involved in the perception of gravity.[provided by RefSeq, May 2009]

NADPH oxidase, EF-hand calcium binding domain 5

Enables proton channel activity and superoxide-generating NAD(P)H oxidase activity. Involved in several processes, including endothelial cell proliferation; proton transmembrane transport; and superoxide anion generation. Located in endoplasmic reticulum and plasma membrane. [provided by Alliance of Genome Resources, Mar 2025]

NADPH oxidase 4

This gene encodes a member of the NOX-family of enzymes that functions as the catalytic subunit the NADPH oxidase complex. The encoded protein is localized to non-phagocytic cells where it acts as an oxygen sensor and catalyzes the reduction of molecular oxygen to various reactive oxygen species (ROS). The ROS generated by this protein have been implicated in numerous biological functions including signal transduction, cell differentiation and tumor cell growth. A pseudogene has been identified on the other arm of chromosome 11. Alternative splicing results in multiple transcript variants.[provided by RefSeq, Jan 2009]

quiescin Q6 sulfhydryl oxidase 2

QSOX2 is a member of the sulfhydryl oxidase/quiescin-6 (Q6) family (QSOX1; MIM 603120) that regulates the sensitization of neuroblastoma cells for IFN-gamma (IFNG; MIM 147570)-induced cell death (Wittke et al., 2003 [PubMed 14633699]).[supplied by OMIM, Jun 2009]

renalase, FAD-dependent amine oxidase

Enables several functions, including NADH binding activity; epinephrine binding activity; and monoamine oxidase activity. Involved in negative regulation of blood pressure and negative regulation of heart rate. Located in extracellular region. Implicated in essential hypertension and hypertension. Biomarker of end stage renal disease. [provided by Alliance of Genome Resources, Mar 2025]

prenylcysteine oxidase 1 like

Predicted to enable prenylcysteine oxidase activity. Predicted to be involved in neutrophil-mediated killing of bacterium and prenylated protein catabolic process. Located in membrane. [provided by Alliance of Genome Resources, Mar 2025]

acyl-CoA oxidase-like

Predicted to enable acyl-CoA oxidase activity; fatty acid binding activity; and flavin adenine dinucleotide binding activity. Predicted to be involved in fatty acid beta-oxidation using acyl-CoA oxidase. Predicted to be located in peroxisomal matrix. Predicted to be active in peroxisome. [provided by Alliance of Genome Resources, Mar 2025]

acyl-CoA oxidase 2, branched chain

The product of this gene belongs to the acyl-CoA oxidase family. It encodes the branched-chain acyl-CoA oxidase which is involved in the degradation of long branched fatty acids and bile acid intermediates in peroxisomes. Deficiency of this enzyme results in the accumulation of branched fatty acids and bile acid intermediates, and may lead to Zellweger syndrome, severe cognitive disability, and death in children. [provided by RefSeq, Mar 2009]

acyl-CoA oxidase 3, pristanoyl

Acyl-Coenzyme A oxidase 3 also know as pristanoyl -CoA oxidase (ACOX3)is involved in the desaturation of 2-methyl branched fatty acids in peroxisomes. Unlike the rat homolog, the human gene is expressed in very low amounts in liver such that its mRNA was undetectable by routine Northern-blot analysis or its product by immunoblotting or by enzyme activity measurements. However the human cDNA encoding a 700 amino acid protein with a peroxisomal targeting C-terminal tripeptide S-K-L was isolated and is thought to be expressed under special conditions such as specific developmental stages or in a tissue specific manner in tissues that have not yet been examined. [provided by RefSeq, Jul 2008]

acyl-CoA oxidase 1, palmitoyl

The protein encoded by this gene is the first enzyme of the fatty acid beta-oxidation pathway, which catalyzes the desaturation of acyl-CoAs to 2-trans-enoyl-CoAs. It donates electrons directly to molecular oxygen, thereby producing hydrogen peroxide. Defects in this gene result in pseudoneonatal adrenoleukodystrophy, a disease that is characterized by accumulation of very long chain fatty acids. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Jul 2008]

sterol-C4-methyl oxidase pseudogene

quiescin Q6 sulfhydryl oxidase 1

This gene encodes a protein that contains domains of thioredoxin and ERV1, members of two long-standing gene families. The gene expression is induced as fibroblasts begin to exit the proliferative cycle and enter quiescence, suggesting that this gene plays an important role in growth regulation. Two transcript variants encoding two different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

polyamine oxidase (exo-N4-amino)

Enables polyamine oxidase activity. Involved in polyamine metabolic process and positive regulation of spermidine biosynthetic process. Predicted to be located in cytosol and peroxisomal matrix. Predicted to be active in cytoplasm. Implicated in lung non-small cell carcinoma. [provided by Alliance of Genome Resources, Mar 2025]

amine oxidase, copper containing 3

This gene encodes a member of the semicarbazide-sensitive amine oxidase family. Copper amine oxidases catalyze the oxidative conversion of amines to aldehydes in the presence of copper and quinone cofactor. The encoded protein is localized to the cell surface, has adhesive properties as well as monoamine oxidase activity, and may be involved in leukocyte trafficking. Alterations in levels of the encoded protein may be associated with many diseases, including diabetes mellitus. A pseudogene of this gene has been described and is located approximately 9-kb downstream on the same chromosome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2013]

spermine oxidase

Polyamines are ubiquitous polycationic alkylamines which include spermine, spermidine, putrescine, and agmatine. These molecules participate in a broad range of cellular functions which include cell cycle modulation, scavenging reactive oxygen species, and the control of gene expression. These molecules also play important roles in neurotransmission through their regulation of cell-surface receptor activity, involvement in intracellular signalling pathways, and their putative roles as neurotransmitters. This gene encodes an FAD-containing enzyme that catalyzes the oxidation of spermine to spermadine and secondarily produces hydrogen peroxide. Multiple transcript variants encoding different isoenzymes have been identified for this gene, some of which have failed to demonstrate significant oxidase activity on natural polyamine substrates. The characterized isoenzymes have distinctive biochemical characteristics and substrate specificities, suggesting the existence of additional levels of complexity in polyamine catabolism. [provided by RefSeq, Jul 2012]

dual oxidase maturation factor 1

Dual oxidases DUOX1 and DUOX2 are NADPH oxidases which are involved in hydrogen peroxide production necessary for thyroid hormonogenesis. They form a heterodimer with specific maturation factors DUOXA1 and DUOXA2, respectively, which is essential for the maturation and function of the DUOX enzyme complexes. This gene encodes the DUOX1 activator or maturation factor DUOXA1. Rat studies identified a bidirectional promoter which controls the transcription of the DUOX1 and DUOXA1 genes. This protein is cotransported to the cell surface when coexpressed with DUOX1 and is retained in the endoplasmic reticulum when expressed without DUOX1 protein. The expression of this gene or the DUOX1 gene is not suppressed by thyroglobulin (Tg), a macromolecular precursor in thyroid hormone synthesis, while the expression of the DUOX2 and DUOXA2 are significantly suppressed by the Tg. This protein is also a p53-regulated neurogenic factor involved in p53 dependent neuronal differentiation. Multiple alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2013]

dual oxidase maturation factor 2

This gene encodes an endoplasmic reticulum protein that is necessary for proper cellular localization and maturation of functional dual oxidase 2. Mutations in this gene have been associated with thyroid dyshormonogenesis 5.[provided by RefSeq, Feb 2010]

amine oxidase, copper containing 4, pseudogene

coproporphyrinogen oxidase

The protein encoded by this gene is the sixth enzyme of the heme biosynthetic pathway. The encoded enzyme is soluble and found in the intermembrane space of mitochondria. This enzyme catalyzes the stepwise oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX, a precursor of heme. Defects in this gene are a cause of hereditary coproporphyria (HCP).[provided by RefSeq, Oct 2009]

amine oxidase, copper containing 1

This gene encodes a metal-binding membrane glycoprotein that oxidatively deaminates putrescine, histamine, and related compounds. The encoded protein is inhibited by amiloride, a diuretic that acts by closing epithelial sodium ion channels. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jan 2013]

lysyl oxidase-like 1

This gene encodes a member of the lysyl oxidase family of proteins. The prototypic member of the family is essential to the biogenesis of connective tissue, encoding an extracellular copper-dependent amine oxidase that catalyzes the first step in the formation of crosslinks in collagen and elastin. The encoded preproprotein is proteolytically processed to generate the mature enzyme. A highly conserved amino acid sequence at the C-terminus end appears to be sufficient for amine oxidase activity, suggesting that each family member may retain this function. The N-terminus is poorly conserved and may impart additional roles in developmental regulation, senescence, tumor suppression, cell growth control, and chemotaxis to each member of the family. Mutations in this gene are associated with exfoliation syndrome. [provided by RefSeq, Jan 2016]

lysyl oxidase-like 2

This gene encodes a member of the lysyl oxidase gene family. The prototypic member of the family is essential to the biogenesis of connective tissue, encoding an extracellular copper-dependent amine oxidase that catalyses the first step in the formation of crosslinks in collagens and elastin. A highly conserved amino acid sequence at the C-terminus end appears to be sufficient for amine oxidase activity, suggesting that each family member may retain this function. The N-terminus is poorly conserved and may impart additional roles in developmental regulation, senescence, tumor suppression, cell growth control, and chemotaxis to each member of the family. [provided by RefSeq, Jul 2008]

lysyl oxidase-like 3

This gene encodes a lysyl oxidase, which likely functions as an amine oxidase and plays a role in the formation of crosslinks in collagens and elastin. Deletion of the related gene in mouse causes neonatal mortality with cleft palate, spine deformity, and defects in collagen organization. A mutation in this gene was found in a family with Stickler syndrome. [provided by RefSeq, Sep 2016]

lysyl oxidase-like 4

This gene encodes a member of the lysyl oxidase gene family. The prototypic member of the family is essential to the biogenesis of connective tissue, encoding an extracellular copper-dependent amine oxidase that catalyses the first step in the formation of crosslinks in collagens and elastin. A highly conserved amino acid sequence at the C-terminus end appears to be sufficient for amine oxidase activity, suggesting that each family member may retain this function. The N-terminus is poorly conserved and may impart additional roles in developmental regulation, senescence, tumor suppression, cell growth control, and chemotaxis to each member of the family. [provided by RefSeq, Jul 2008]

pipecolic acid oxidase

Enables L-pipecolate oxidase activity and sarcosine oxidase activity. Involved in L-lysine catabolic process to acetyl-CoA via L-pipecolate. Located in peroxisome. [provided by Alliance of Genome Resources, Mar 2025]

aldehyde oxidase 1

Aldehyde oxidase produces hydrogen peroxide and, under certain conditions, can catalyze the formation of superoxide. Aldehyde oxidase is a candidate gene for amyotrophic lateral sclerosis. [provided by RefSeq, Jul 2008]

proline dehydrogenase (oxidase) 1

This gene encodes a mitochondrial protein that catalyzes the first step in proline degradation. Mutations in this gene are associated with hyperprolinemia type 1 and susceptibility to schizophrenia 4 (SCZD4). This gene is located on chromosome 22q11.21, a region which has also been associated with the contiguous gene deletion syndromes, DiGeorge and CATCH22. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2010]

gulonolactone (L-) oxidase, pseudogene

This gene is nonfunctional in humans and other primates. In most mammalian species the corresponding gene encodes L-gulono-gamma-lactone oxidase which catalyzes the last step of ascorbic acid biosynthesis. The human gene is a remnant that lacks five of twelve exons found in functional rodent genes. The loss of enzyme activity results in hypoascorbemia or the inability to synthesize vitamin C. [provided by RefSeq, Nov 2010]

NADPH oxidase 4 pseudogene

aldehyde oxidase 2 pseudogene

D-aspartate oxidase

The protein encoded by this gene is a peroxisomal flavoprotein that catalyzes the oxidative deamination of D-aspartate and N-methyl D-aspartate. Flavin adenine dinucleotide or 6-hydroxyflavin adenine dinucleotide can serve as the cofactor in this reaction. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2019]

prenylcysteine oxidase 1 pseudogene

NADPH oxidase organizer 1

This gene encodes an NADPH oxidase (NOX) organizer, which positively regulates NOX1 and NOX3. The protein contains a PX domain and two SH3 domains. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jun 2012]

proline dehydrogenase (oxidase) 2

The protein encoded by this gene catalyzes the first step in the catabolism of trans-4-hydroxy-L-proline, an amino acid derivative obtained through food intake and collagen turnover. One of the downstream products of this catabolism is glyoxylate, which in people with disorders of glyoxalate metabolism can lead to an increase in oxalate levels and the formation of calcium-oxalate kidney stones. Therefore, this gene may serve as a therapeutic target against primary hyperoxalurias (PH). This gene is similar to proline dehydrogenase (oxidase) 1, a mitochondrial enzyme that catalyzes the first step in proline catabolism. [provided by RefSeq, Jan 2017]

membrane primary amine oxidase-like

sulfite oxidase pseudogene

prenylcysteine oxidase 1

Prenylcysteine is released during the degradation of prenylated proteins. PCYOX1 catalyzes the degradation of prenylcysteine to yield free cysteines and a hydrophobic isoprenoid product (Tschantz et al., 1999 [PubMed 10585463]).[supplied by OMIM, Mar 2008]

lysyl oxidase

This gene encodes a member of the lysyl oxidase family of proteins. Alternative splicing results in multiple transcript variants, at least one of which encodes a preproprotein that is proteolytically processed to generate a regulatory propeptide and the mature enzyme. The copper-dependent amine oxidase activity of this enzyme functions in the crosslinking of collagens and elastin, while the propeptide may play a role in tumor suppression. In addition, defects in this gene have been linked with predisposition to thoracic aortic aneurysms and dissections. [provided by RefSeq, Jul 2016]

D-amino-acid oxidase

This gene encodes the peroxisomal enzyme D-amino acid oxidase. The enzyme is a flavoprotein which uses flavin adenine dinucleotide (FAD) as its prosthetic group. Its substrates include a wide variety of D-amino acids, but it is inactive on the naturally occurring L-amino acids. Its biological function is not known; it may act as a detoxifying agent which removes D-amino acids that accumulate during aging. In mice, it degrades D-serine, a co-agonist of the NMDA receptor. This gene may play a role in the pathophysiology of schizophrenia. [provided by RefSeq, Jul 2008]

protoporphyrinogen oxidase

This gene encodes the penultimate enzyme of heme biosynthesis, which catalyzes the 6-electron oxidation of protoporphyrinogen IX to form protoporphyrin IX. Mutations in this gene cause variegate porphyria, an autosomal dominant disorder of heme metabolism resulting from a deficiency in protoporphyrinogen oxidase, an enzyme located on the inner mitochondrial membrane. Alternatively spliced transcript variants encoding the same protein have been identified. [provided by RefSeq, Jul 2008]

NADPH oxidase activator 1

This gene encodes a protein which activates NADPH oxidases, enzymes which catalyze a reaction generating reactive oxygen species. The encoded protein contains four N-terminal tetratricopeptide domains and a C-terminal Src homology 3 domain. Interaction between the encoded protein and proteins in the oxidase regulatory complex occur via the tetratricopeptide domains. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2011]

sulfite oxidase

Sulfite oxidase is a homodimeric protein localized to the intermembrane space of mitochondria. Each subunit contains a heme domain and a molybdopterin-binding domain. The enzyme catalyzes the oxidation of sulfite to sulfate, the final reaction in the oxidative degradation of the sulfur amino acids cysteine and methionine. Sulfite oxidase deficiency results in neurological abnormalities which are often fatal at an early age. Alternative splicing results in multiple transcript variants encoding identical proteins. [provided by RefSeq, Jul 2008]

hydroxyacid oxidase 2 (long chain)

This gene is one of three related genes that have 2-hydroxyacid oxidase activity. The encoded protein localizes to the peroxisome has the highest activity toward the substrate 2-hydroxypalmitate. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

aldehyde oxidase 3, pseudogene

Predicted to enable aldehyde oxidase activity; electron transfer activity; and molybdenum ion binding activity. Predicted to be located in cytosol. [provided by Alliance of Genome Resources, Mar 2025]

cytochrome c, somatic pseudogene 38

cytochrome c, somatic pseudogene 39

cytochrome c, somatic pseudogene 34

cytochrome c, somatic pseudogene 35

cytochrome c, somatic pseudogene 30

cytochrome c, somatic pseudogene 32

cytochrome P450, family 2, subfamily D, polypeptide 6

This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and is known to metabolize as many as 25% of commonly prescribed drugs. Its substrates include antidepressants, antipsychotics, analgesics and antitussives, beta adrenergic blocking agents, antiarrythmics and antiemetics. The gene is highly polymorphic in the human population; certain alleles result in the poor metabolizer phenotype, characterized by a decreased ability to metabolize the enzyme's substrates. Some individuals with the poor metabolizer phenotype have no functional protein since they carry 2 null alleles whereas in other individuals the gene is absent. This gene can vary in copy number and individuals with the ultrarapid metabolizer phenotype can have 3 or more active copies of the gene. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2014]