Pathway candidateNCBI-verifiedprotein-coding

CYP1A1

cytochrome P450 family 1 subfamily A member 1

NCBI Gene: 1543 Ensembl GeneCards UniProt: P04798

Pathway candidate — not linked to PFS or PSSD by any record here

CYP1A1 is in the library because it belongs to the drug metabolism family. No study, report or commentary in the corpus names it, so a variant in CYP1A1 is not, by itself, evidence of anything related to post-drug syndromes.

Gene summary

A protein-coding gene on chromosome 15 (drug metabolism (phase i)). This gene, CYP1A1, 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.

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Cytochrome P450 1A1
Function (excerpt): A cytochrome P450 monooxygenase involved in the metabolism of various endogenous substrates, including fatty acids, steroid hormones and vitamins. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the hydroxylation of carbon-hydrogen bonds. Exhibits high catalytic activity for the formation of hydroxyestrogens from estrone (E1) and 17beta-estradiol (E2), namely 2-hydroxy E1 and E2, as well as D-ring hydroxylated E1 and E2 at the C15-alpha and C16-alpha positions. Displays different regioselectivities for polyunsaturated fatty acids (PUFA) hydroxylation. Catalyzes the epoxidation of double bonds of certain PUFA. Converts arachidonic acid toward epoxyeicosatrienoic acid (EET) regioisomers, 8,9-, 11,12-, and 14,15-EET, that function as lipid mediators in the vascular system.
Pathway: Steroid hormone biosynthesis. Lipid metabolism; fatty acid metabolism. Cofactor metabolism; retinol metabolism.
Subcellular location: Endoplasmic reticulum membrane; Mitochondrion inner membrane; Microsome membrane; Cytoplasm.
Tissue specificity: Lung, lymphocytes and placenta.

Source: UniProtKB/Swiss-Prot P04798, release 2026_03, licensed CC BY 4.0. This is the protein’s normal biology, not evidence about post-drug syndromes; associated conditions are inherited disorders of the gene, not PFS, PSSD or PRSD.

Why its pathway is in the library

Phase I enzymes determine exposure to finasteride, SSRIs, and other implicated drugs; variation here shapes the likelihood and persistence of adverse effects.

Written for the whole drug metabolism family, not for CYP1A1 specifically.

Mentioned in 0 corpus records

No corpus record names CYP1A1 directly yet. It is in the library because it sits in a pathway the corpus tracks (Drug metabolism).

Also in drug metabolism (phase i)

All 23 genes

Browse by family on the gene families page.

Gene summary

Source: NCBI Gene, accessed 2026-10-07.

Protein reference (UniProt)

Protein: Cytochrome P450 1A1
Function (excerpt): A cytochrome P450 monooxygenase involved in the metabolism of various endogenous substrates, including fatty acids, steroid hormones and vitamins. Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate, and reducing the second into a water molecule, with two electrons provided by NADPH via cytochrome P450 reductase (NADPH--hemoprotein reductase). Catalyzes the hydroxylation of carbon-hydrogen bonds. Exhibits high catalytic activity for the formation of hydroxyestrogens from estrone (E1) and 17beta-estradiol (E2), namely 2-hydroxy E1 and E2, as well as D-ring hydroxylated E1 and E2 at the C15-alpha and C16-alpha positions. Displays different regioselectivities for polyunsaturated fatty acids (PUFA) hydroxylation. Catalyzes the epoxidation of double bonds of certain PUFA. Converts arachidonic acid toward epoxyeicosatrienoic acid (EET) regioisomers, 8,9-, 11,12-, and 14,15-EET, that function as lipid mediators in the vascular system.
Pathway: Steroid hormone biosynthesis. Lipid metabolism; fatty acid metabolism. Cofactor metabolism; retinol metabolism.
Subcellular location: Endoplasmic reticulum membrane; Mitochondrion inner membrane; Microsome membrane; Cytoplasm.
Tissue specificity: Lung, lymphocytes and placenta.