CYP2D6

CYP2D6
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
AliasesCYP2D6, CPD6, CYP2D, CYP2D7AP, CYP2D7BP, CYP2D7P2, CYP2D8P2, CYP2DL1, CYPIID6, P450-DB1, P450C2D, P450DB1, cytochrome P450 family 2 subfamily D member 6, Cytochrome P450 2D6
External IDsOMIM: 124030; MGI: 1929474; HomoloGene: 133550; GeneCards: CYP2D6; OMA:CYP2D6 - orthologs
Orthologs
SpeciesHumanMouse
Entrez

1565

56448

Ensembl

ENSMUSG00000061740

UniProt

P10635

Q9JKY7

RefSeq (mRNA)

NM_000106
NM_001025161

NM_001163472
NM_019823

RefSeq (protein)

NP_000097
NP_001020332

NP_001156944
NP_062797

Location (UCSC)Chr 22: 42.13 – 42.13 MbChr 15: 82.25 – 82.26 Mb
PubMed search
Wikidata
View/Edit HumanView/Edit Mouse

Cytochrome P450 2D6 (CYP2D6) is an enzyme that in humans is encoded by the CYP2D6 gene. CYP2D6 is primarily expressed in the liver. It is also highly expressed in areas of the central nervous system, including the substantia nigra.

CYP2D6, a member of the cytochrome P450 mixed-function oxidase system, is one of the most important enzymes involved in the metabolism of xenobiotics in the body. In particular, CYP2D6 is responsible for the metabolism and elimination of approximately 25% of clinically used drugs, via the addition or removal of certain functional groups – specifically, hydroxylation, demethylation, and dealkylation. CYP2D6 also activates some prodrugs. This enzyme also metabolizes several endogenous substances, such as N,N-Dimethyltryptamine, hydroxytryptamines, neurosteroids, and both m-tyramine and p-tyramine which CYP2D6 metabolizes into dopamine in the brain and liver.

Considerable variation exists in the efficiency and amount of CYP2D6 enzyme produced between individuals. Hence, for drugs that are metabolized by CYP2D6 (that is, are CYP2D6 substrates), certain individuals will eliminate these drugs quickly (ultrarapid metabolizers) while others slowly (poor metabolizers). If a drug is metabolized too quickly, it may decrease the drug's efficacy while if the drug is metabolized too slowly, toxicity may result. So, the dose of the drug may have to be adjusted to take into account of the speed at which it is metabolized by CYP2D6. Individuals who exhibit an ultrarapid metabolizer phenotype, metabolize prodrugs, such as codeine or tramadol, more rapidly, leading to higher than therapeutic levels. A case study of the death of an infant breastfed by an ultrarapid metabolizer mother taking codeine impacted postnatal pain relief clinical practices, but was later debunked. These drugs may also cause serious toxicity in ultrarapid metabolizer patients when used to treat other post-operative pain, such as after tonsillectomy. Other drugs may function as inhibitors of CYP2D6 activity or inducers of CYP2D6 enzyme expression that will lead to decreased or increased CYP2D6 activity respectively. If such a drug is taken at the same time as a second drug that is a CYP2D6 substrate, the first drug may affect the elimination rate of the second through what is known as a drug-drug interaction.