Pathway candidateNCBI-verifiedprotein-coding

ABCG2

ATP binding cassette subfamily G member 2 (JR blood group)

NCBI Gene: 9429 Ensembl GeneCards UniProt: Q9UNQ0

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

ABCG2 is in the library because it belongs to the drug transporters family. No study, report or commentary in the corpus names it, so a variant in ABCG2 is not, by itself, evidence of anything related to post-drug syndromes.

Gene summary

A protein-coding gene on chromosome 4 (drug and xenobiotic transporters). The membrane-associated protein encoded by this gene is included in the superfamily of ATP-binding cassette (ABC) transporters. ABC proteins transport various molecules across extra- and intra-cellular membranes.

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

Protein reference (UniProt)

Protein: Broad substrate specificity ATP-binding cassette transporter ABCG2
Function (excerpt): Broad substrate specificity ATP-dependent transporter of the ATP-binding cassette (ABC) family that actively extrudes a wide variety of physiological compounds, dietary toxins and xenobiotics from cells. Involved in porphyrin homeostasis, mediating the export of protoporphyrin IX (PPIX) from both mitochondria to cytosol and cytosol to extracellular space, it also functions in the cellular export of heme. Also mediates the efflux of sphingosine-1-P from cells. Acts as a urate exporter functioning in both renal and extrarenal urate excretion. In kidney, it also functions as a physiological exporter of the uremic toxin indoxyl sulfate (By similarity). Also involved in the excretion of steroids like estrone 3-sulfate/E1S, 3beta-sulfooxy-androst-5-en-17-one/DHEAS, and other sulfate conjugates. Mediates the secretion of the vitamins riboflavin and biotin into milk (By similarity).
Subcellular location: Cell membrane; Apical cell membrane; Mitochondrion membrane.
Tissue specificity: Highly expressed in placenta. Low expression in small intestine, liver and colon. Expressed in brain (at protein level).

Source: UniProtKB/Swiss-Prot Q9UNQ0, 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

Transporters set systemic exposure to finasteride/SSRIs and clear conjugated steroid metabolites — directly relevant to both drug pharmacokinetics and Powers' clearance-centered PFS mechanism.

Written for the whole drug transporters family, not for ABCG2 specifically.

Mentioned in 0 corpus records

No corpus record names ABCG2 directly yet. It is in the library because it sits in a pathway the corpus tracks (Drug transporters).

Also in drug and xenobiotic transporters

All 62 genes

Browse by family on the gene families page.

Gene summary

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

Protein reference (UniProt)

Protein: Broad substrate specificity ATP-binding cassette transporter ABCG2
Function (excerpt): Broad substrate specificity ATP-dependent transporter of the ATP-binding cassette (ABC) family that actively extrudes a wide variety of physiological compounds, dietary toxins and xenobiotics from cells. Involved in porphyrin homeostasis, mediating the export of protoporphyrin IX (PPIX) from both mitochondria to cytosol and cytosol to extracellular space, it also functions in the cellular export of heme. Also mediates the efflux of sphingosine-1-P from cells. Acts as a urate exporter functioning in both renal and extrarenal urate excretion. In kidney, it also functions as a physiological exporter of the uremic toxin indoxyl sulfate (By similarity). Also involved in the excretion of steroids like estrone 3-sulfate/E1S, 3beta-sulfooxy-androst-5-en-17-one/DHEAS, and other sulfate conjugates. Mediates the secretion of the vitamins riboflavin and biotin into milk (By similarity).
Subcellular location: Cell membrane; Apical cell membrane; Mitochondrion membrane.
Tissue specificity: Highly expressed in placenta. Low expression in small intestine, liver and colon. Expressed in brain (at protein level).