Component
Human CYP2R1 L99P variant
Patient-derived Leu99Pro substitution studied in vitamin D 25-hydroxylation assays.
1 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
What it acts on
The patient-derived human CYP2R1 Leu99Pro variant lost detectable D3 25-hydroxylase activity in the expression assays.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- false
- evidence_location
- Results, Figures 3-5 and primary abstract.
- experimental_model
- Patient-derived allele expressed in cells
- exposure
- L99P versus wild-type CYP2R1; D3 biochemical/reporting assays.
- limitations
- The patient had residual circulating metabolites and responded to D2 treatment; this does not prove zero whole-body activation or zero residual D2 activity.
- nutrient
- Vitamin D2 and D3 · Vitamin D2 and D3
- nutrient_topic
- Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin D2 and D3
- organism
- Homo sapiens protein
- plain_language
- A CYP2R1 mutation can break the first D3 activation step.
- primary_references
- [cheng2004] Genetic evidence that the human CYP2R1 enzyme is a key vitamin D 25-hydroxylase. (2004). https://pubmed.ncbi.nlm.nih.gov/15128933/ DOI: 10.1073/pnas.0402490101
- tissue_or_cell_type
- heterologous expression model
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Vitamin D2 and D3: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 362–375
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Patient-derived allele expressed in cells · source_derived_draft · unverified_draft
### vd-act-cyp2r1-l99p The patient-derived human CYP2R1 Leu99Pro variant lost detectable D3 25-hydroxylase activity in the expression assays. Condition category: machinery_impairment nutrient_topic: Vitamin D2 and D3 research collection; topical membership is not evidence of a direct dietary effect. plain_language: A CYP2R1 mutation can break the first D3 activation step. organism: Homo sapiens protein tissue_or_cell_type: heterologous expression model experimental_model: Patient-derived allele expressed in cells limitations: The patient had residual circulating metabolites and responded to D2 treatment; this does not prove zero whole-body activation or zero residual D2 activity. exposure: L99P versus wild-type CYP2R1; D3 biochemical/reporting assays. cross_nutrient: false evidence_location: Results, Figures 3-5 and primary abstract. nutrient: Vitamin D2 and D3 [cheng2004] Genetic evidence that the human CYP2R1 enzyme is a key vitamin D 25-hydroxylase. (2004). https://pubmed.ncbi.nlm.nih.gov/15128933/ DOI: 10.1073/pnas.0402490101
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.