Référence des biomarqueurs

Ce qui est mesuré.
Pourquoi ça compte.

Les analyses standard ont été conçues pour détecter la maladie. BioMarco teste pour l'optimisation — la différence entre « rien ne va mal » et « tout fonctionne ». Sélectionnez votre mode ci-dessous.

Cardiovasculaire Métabolique Génomique

Risque cardiovasculaire

L'athérosclérose — l'accumulation lente de plaque dans les parois artérielles — commence des décennies avant une crise cardiaque ou un AVC. Ces marqueurs identifient le processus tôt, quand l'intervention est la plus efficace.

Essentiel — à prescrire à chaque première visite
ApoB
Le vrai compte des particules de cholestérol nocives dans votre sang — plus précis que le cholestérol LDL standard.
Dénombrement direct de toutes les particules athérogènes (LDL, VLDL, IDL, Lp(a)) par immunodosage. Un ApoB par particule — la mesure définitive de la charge particulaire.
Essentiel +

Pourquoi c'est important

Chaque particule athérogène porte exactement une molécule ApoB. Mesurer l'ApoB donne le compte précis des particules conduisant à la formation de plaque — quelque chose que le LDL-C ne peut pas faire.

Valeurs cibles

Standard: <130 mg/dL Optimal: <80 mg/dL

Patients à haut risque (événement cardiovasculaire antérieur, diabète, élévation de Lp(a)) : cible <60 mg/dL

Profondeur mécanistique

Les particules contenant ApoB pénètrent l'intima artérielle selon le nombre de particules, pas la teneur en cholestérol. Les petites particules LDL denses pénètrent plus facilement et sont plus susceptibles à l'oxydation.

Interactions clés

  • Le génotype APOE4 amplifie significativement le risque lié à l'ApoB
  • La résistance à l'insuline élève l'ApoB via une sécrétion accrue de VLDL
  • Les statines réduisent l'ApoB de ~30-50% — vérifier par un nouveau test post-traitement
  • Les graisses saturées alimentaires augmentent l'ApoB dans la plupart des génotypes
Lp(a)
Une particule déterminée génétiquement qui augmente considérablement le risque cardiovasculaire — la plupart des gens ne l'ont jamais fait tester.
Lipoprotéine(a) — une particule ressemblant au LDL avec une queue apolipoprotéine(a) supplémentaire conférant des propriétés thrombogènes et athérogènes uniques indépendantes du mode de vie.
Essentiel +

Pourquoi c'est important

Le Lp(a) est déterminé à 80-90% génétiquement — l'alimentation et l'exercice ont un impact minimal. Un Lp(a) élevé (au-dessus de 50 mg/dL ou 125 nmol/L) double approximativement le risque cardiovasculaire indépendamment du LDL-C.

Valeurs cibles

Standard: <75 nmol/L Optimal: <30 nmol/L

Note : les unités varient (mg/dL vs nmol/L). Toujours confirmer les unités avec votre laboratoire.

Profondeur mécanistique

The apolipoprotein(a) tail structurally resembles plasminogen, competitively inhibiting fibrinolysis and promoting thrombosis. Lp(a) also preferentially accumulates in arterial walls, oxidizes phospholipids, promotes macrophage foam cell formation, and stimulates smooth muscle proliferation — multiple parallel mechanisms of harm.

Interactions clés

  • PCSK9 inhibitors reduce Lp(a) ~20-30%
  • High-dose niacin reduces Lp(a) but cardiovascular outcome benefit unclear
  • RNA-based therapies (pelacarsen) in late-stage trials — watch this space
  • Elevated Lp(a) changes ApoB target — push lower
hs-CRP
Une mesure de l'inflammation silencieuse dans votre corps — des niveaux élevés signalent un risque cardiovasculaire même quand le cholestérol semble normal.
Protéine C-réactive haute sensibilité — réactant de phase aiguë hépatique reflétant le tonus inflammatoire systémique, prédicteur indépendant du risque cardiovasculaire.
Essentiel +

Pourquoi c'est important

Atherosclerosis is fundamentally an inflammatory disease. CRP reflects the inflammatory environment that allows LDL particles to oxidize and embed in arterial walls. The JUPITER trial showed that people with normal LDL-C but elevated hs-CRP had dramatically reduced cardiovascular events with statin therapy — proving inflammation matters independent of cholesterol.

Valeurs cibles

Standard: <3.0 mg/L Optimal: <1.0 mg/L

Des valeurs au-dessus de 10 mg/L suggèrent une infection ou blessure aiguë — retester une fois résolue.

Profondeur mécanistique

CRP is produced by the liver in response to IL-6 signaling from adipose tissue, macrophages, and damaged endothelium. It activates complement, promotes LDL uptake by macrophages, and directly stimulates endothelial expression of adhesion molecules. It is both a marker and a mediator of vascular inflammation.

Interactions clés

  • Visceral fat is the primary driver in metabolic syndrome
  • Omega-3 supplementation consistently reduces hs-CRP
  • Sleep deprivation acutely elevates CRP
  • Periodontal disease is a significant underappreciated source
Homocysteine
Un acide aminé qui endommage les parois artérielles lorsqu'il est élevé — directement lié à votre statut en vitamines B et aux variantes génétiques de méthylation.
Sulfur-containing amino acid at the intersection of the methionine cycle and transsulfuration pathway — elevated levels reflect methylation insufficiency and independently predict cardiovascular and cognitive risk.
Essentiel +

Pourquoi c'est important

Elevated homocysteine directly damages endothelial cells, promotes oxidative stress, impairs nitric oxide production, and increases thrombotic risk. It bridges cardiovascular and methylation health — a single marker telling you about vascular risk AND whether your B12, folate, and B6 pathways are functioning. Often elevated silently for years.

Valeurs cibles

Standard: <15 µmol/L Optimal: 6–9 µmol/L

Des niveaux au-dessus de 12 µmol/L justifient une investigation B12, folate, B6 et un génotypage MTHFR.

Profondeur mécanistique

Homocysteine accumulates when the methionine cycle stalls — either from B12/folate deficiency impairing remethylation, or B6 deficiency impairing transsulfuration to cysteine. MTHFR variants (especially C677T homozygous) reduce 5-MTHF availability, slowing remethylation. The result is SAH accumulation which product-inhibits all methyltransferase reactions.

Interactions clés

  • MTHFR C677T homozygous raises homocysteine ~25%
  • Metformin depletes B12, raising homocysteine over time
  • 5-MTHF (not folic acid) is the correct supplementation for MTHFR variants
  • Trimethylglycine (TMG) provides an alternative remethylation route via BHMT
Avancé — ajouts à haut rendement
Oxidized LDL
The damaged form of LDL that directly triggers plaque buildup — more dangerous than regular LDL cholesterol.
ox-LDL — LDL particles modified by reactive oxygen species, recognized by scavenger receptors on macrophages initiating foam cell formation and atherogenesis.
Avancé +

Pourquoi c'est important

Not all LDL is equally dangerous. LDL only becomes atherogenic after oxidation. Oxidized LDL is taken up by macrophages uncontrollably, forming foam cells — the core of arterial plaque. Someone with moderate ApoB but high ox-LDL is in a more pro-atherogenic environment than someone with high ApoB but low oxidative stress.

Valeurs cibles

Optimal: <60 U/L

Reference ranges vary by lab. Trend over time matters as much as absolute value.

Profondeur mécanistique

Small dense LDL particles are preferentially oxidized due to lower antioxidant content and longer plasma residence time. Myeloperoxidase from activated neutrophils is a primary oxidizing agent in the arterial wall. Elevated ox-LDL predicts cardiovascular events independently of LDL-C and is a direct readout of oxidative stress burden in the vascular compartment.

Interactions clés

  • Vitamin E, CoQ10, polyphenols reduce LDL oxidation
  • Smoking dramatically increases ox-LDL
  • Omega-3 index inversely correlates with ox-LDL
  • High fructose intake increases ox-LDL via uric acid and ROS generation
ApoA1
The protein that makes HDL work — measures your protective cholesterol capacity more accurately than HDL-C alone.
Primary structural apolipoprotein of HDL particles — activates LCAT, facilitates ABCA1-mediated cholesterol efflux from macrophages, enabling reverse cholesterol transport.
Avancé +

Pourquoi c'est important

HDL-C measures cholesterol cargo inside HDL particles. ApoA1 counts the functional particles doing the protective work. The ApoB:ApoA1 ratio captures both sides of the atherogenic equation simultaneously — particle burden vs. protective capacity. Insulin resistance typically suppresses ApoA1 while raising ApoB, creating a doubly dangerous divergence.

Valeurs cibles

Standard: >120 mg/dL (women) >110 mg/dL (men) ApoB:ApoA1 ratio <0.7

Profondeur mécanistique

ApoA1 activates LCAT which esterifies free cholesterol within HDL, loading the particle for hepatic delivery. It binds ABCA1 on macrophage surfaces to initiate cholesterol efflux from foam cells. HDL particle functionality — not just cholesterol content — determines atheroprotective capacity. ApoA1 is the functional proxy for that capacity.

Interactions clés

  • Exercise is the most consistent ApoA1 raiser
  • Insulin resistance suppresses hepatic ApoA1 synthesis
  • Alcohol raises HDL-C but not necessarily ApoA1 functionality
  • PPARα agonists (fibrates) upregulate ApoA1 transcription

Optimisation métabolique

Le dysfonctionnement métabolique est en amont de presque toutes les maladies chroniques majeures — maladies cardiovasculaires, diabète de type 2, Alzheimer, certains cancers et plus. Ces marqueurs identifient les inefficacités bien avant que la maladie se manifeste.

Essentiel — à prescrire à chaque première visite
Fasting Insulin
Le marqueur métabolique le plus important que la plupart des médecins ne prescrivent jamais — révèle la résistance à l'insuline des années avant que la glycémie devienne anormale.
Insuline sérique à jeun — le signal le plus précoce et quantifiable de la résistance à l'insuline, détectant la compensation des cellules bêta avant que la dysrégulation glycémique soit apparente.
Essentiel +

Pourquoi c'est important

Insulin resistance can be present for 10-15 years before fasting glucose rises. During that window the pancreas compensates by producing more insulin to overcome resistance — glucose stays normal, but insulin is elevated. Measuring fasting insulin catches this compensatory state. It's the difference between detecting a problem at year 2 versus year 12.

Valeurs cibles

Standard: <25 µIU/mL Optimal: <6 µIU/mL

Combiner avec la glycémie à jeun pour calculer le HOMA-IR pour une image complète.

Profondeur mécanistique

Insulin resistance begins in skeletal muscle (reduced GLUT4 translocation), progresses to hepatic insulin resistance (failure to suppress gluconeogenesis), and finally manifests as beta-cell exhaustion and glucose elevation. Fasting insulin captures the early muscle/liver resistance phase. Chronically elevated insulin drives VLDL overproduction, suppresses lipolysis, promotes fat storage, and activates mTOR — accelerating aging pathways.

Interactions clés

  • HOMA-IR = (glycémie à jeun × insuline à jeun) / 405 — cible <1,5
  • Ratio triglycérides:HDL >2,0 est un substitut quand l'insuline n'est pas disponible
  • L'alimentation à temps restreint réduit constamment l'insuline à jeun
  • L'entraînement en résistance améliore la sensibilité à l'insuline en 2 semaines
Uric Acid
Bien plus qu'un marqueur de goutte — l'acide urique élevé prédit la résistance à l'insuline, l'hypertension et le risque cardiovasculaire, souvent lié à l'apport en fructose.
End product of purine catabolism via xanthine oxidase — a metabolic readout of fructose load, ATP depletion, and oxidative stress with direct mechanistic links to insulin resistance and endothelial dysfunction.
Essentiel +

Pourquoi c'est important

Uric acid above 5.5 mg/dL inhibits endothelial nitric oxide synthase, directly impairing vascular function. It promotes insulin resistance independently, drives hepatic fat accumulation, and is a direct readout of how much fructose the liver is processing. The old gout framing badly undersells this marker's metabolic significance.

Valeurs cibles

Standard: <7.0 mg/dL (men) Optimal: 3.5–5.0 mg/dL

Les valeurs de référence ont été établies pour prévenir la goutte — pas pour optimiser la santé métabolique.

Profondeur mécanistique

Fructose phosphorylation by fructokinase depletes intracellular ATP unregulated, generating AMP which is catabolized to uric acid. Intracellular uric acid is pro-oxidant and activates a fat-storage switch via ChREBP and lipogenic enzymes. Simultaneously uric acid inhibits eNOS by competing with arginine for tetrahydrobiopterin, reducing NO and raising blood pressure. Richard Johnson's research group has detailed this pathway extensively.

Interactions clés

  • Fructose (including fruit juice, HFCS, honey, agave) is primary driver
  • Thiazide diuretics raise uric acid — clinically important for pharmacists
  • Losartan uniquely lowers uric acid among ARBs
  • Low-dose aspirin raises uric acid via competing renal tubular secretion
  • Allopurinol being studied for cardiovascular benefit beyond gout
GGT
Une enzyme hépatique qui s'élève avant les tests hépatiques conventionnels — un signal d'alerte précoce pour le stress oxydatif, la surcharge de détoxification et le dysfonctionnement métabolique.
Gamma-glutamyl transferase — membrane-bound enzyme reflecting hepatic oxidative stress, glutathione turnover, and Phase II detoxification capacity. Rises before ALT in many metabolic conditions.
Essentiel +

Pourquoi c'est important

GGT is the most sensitive early marker of hepatic metabolic stress — it rises before ALT or AST in NAFLD, insulin resistance, and environmental toxin burden. Elevated GGT also independently predicts cardiovascular mortality, type 2 diabetes, and all-cause mortality. Most clinicians ignore it until it's dramatically elevated. In precision health it's an early warning system.

Valeurs cibles

Standard: <55 U/L (men) Optimal: <25 U/L

Même dans la plage normale, un GGT plus élevé est associé à un risque métabolique croissant.

Profondeur mécanistique

GGT catalyzes the transfer of glutamyl groups from glutathione to peptides and amino acids — a critical step in glutathione recycling and cysteine supply for new GSH synthesis. When oxidative load is high, GGT is upregulated to meet demand, making it a proxy for total oxidative burden. It also reflects CYP450 enzyme induction, tracking xenobiotic detoxification activity in the liver.

Interactions clés

  • Alcohol is the most potent GGT inducer — even moderate intake elevates it
  • NAC supplementation supports glutathione and may reduce GGT
  • Environmental toxin exposure (pesticides, heavy metals) raises GGT
  • Elevated GGT + normal ALT often = early NAFLD or metabolic syndrome
Vitamin D (25-OH)
Plus hormone que vitamine — la carence est liée aux maladies cardiovasculaires, à la résistance à l'insuline, à la dysfonction immunitaire et aux troubles de l'humeur. Quasi universelle dans les climats nordiques.
25-hydroxyvitamin D — the stable circulating storage form reflecting total body vitamin D status, precursor to the active 1,25(OH)2D3 hormone binding nuclear VDR receptors in virtually every tissue.
Essentiel +

Pourquoi c'est important

Vitamin D receptors exist in over 35 tissues. Deficiency impairs insulin secretion, raises parathyroid hormone, increases cardiovascular risk, suppresses immune regulation, and reduces muscle strength. In northern latitudes like New Brunswick deficiency is nearly universal from October through April. Standard labs flag deficiency at <50 nmol/L — optimal for health is considerably higher.

Valeurs cibles

Standard: >50 nmol/L Optimal: 100–150 nmol/L

Supplémenter avec D3 + K2 (MK-7). Retester après 3 mois pour calibrer la dose.

Profondeur mécanistique

VDR variants (Bsm1, Fok1, Taq1, Cdx2 polymorphisms) significantly affect vitamin D receptor sensitivity — two people with identical serum 25-OH D3 can have dramatically different tissue responses. VDR genotyping explains why some patients need 5000 IU/day to maintain 125 nmol/L while others maintain that on 1000 IU. This is where genomics directly personalizes dosing.

Interactions clés

  • VDR variants determine individual dose requirements
  • Magnesium is required for vitamin D activation — deficiency blunts response
  • K2 (MK-7) directs calcium to bone rather than soft tissue
  • Obesity sequesters vitamin D in adipose — higher doses needed
Avancé — portrait métabolique approfondi
Magnesium (RBC)
Le magnésium sérique est presque inutile — le magnésium érythrocytaire mesure ce qui est réellement à l'intérieur de vos cellules, là où le magnésium fait son travail.
Erythrocyte magnesium — intracellular Mg²⁺ status reflecting true tissue availability. Cofactor in 300+ enzymatic reactions including ATP synthesis, DNA repair, and methylation cycle activity.
Avancé +

Pourquoi c'est important

Magnesium is a cofactor in over 300 enzymatic reactions — including every ATP-generating reaction, DNA and RNA synthesis, glutathione production, and multiple methylation cycle steps. Serum magnesium is tightly regulated and stays normal until depletion is severe. RBC magnesium reveals the true intracellular status. Deficiency is estimated to affect 50-60% of the population.

Valeurs cibles

Standard: 4.0–6.4 mg/dL (RBC) Optimal: 5.5–6.5 mg/dL (RBC)

Glycinate ou malate de magnésium préférés pour l'absorption par rapport aux formes d'oxyde.

Profondeur mécanistique

ATP exists biologically as Mg-ATP — magnesium chelation is required for ATP stability and recognition by kinases. Mg²⁺ is a cofactor for COMT (catecholamine metabolism), methionine adenosyltransferase (SAM synthesis), and DNA methyltransferases. Low intracellular magnesium impairs methylation capacity independent of B vitamin status — an underappreciated connection.

Interactions clés

  • PPIs reduce magnesium absorption — clinically significant on long-term use
  • High-dose vitamin D increases magnesium demand for activation
  • Stress hormones (cortisol, adrenaline) deplete intracellular magnesium
  • COMT variants increase magnesium demand for catecholamine clearance
Omega-3 Index
Mesure l'EPA et le DHA dans vos globules rouges — un indicateur direct de votre statut de protection cardiovasculaire et inflammatoire par les oméga-3.
RBC EPA + DHA as % of total fatty acids — a stable 3-month integrated measure of omega-3 tissue status with strong epidemiological links to cardiovascular, cognitive, and inflammatory outcomes.
Avancé +

Pourquoi c'est important

The omega-3 index predicts sudden cardiac death risk with similar power to LDL-C — yet almost no standard panels include it. A low index (<4%) roughly doubles cardiovascular risk. Target above 8%. Most North Americans sit at 4-5%. It's also the correct way to monitor fish oil supplementation — serum omega-3 fluctuates daily, RBC levels reflect actual tissue incorporation over months.

Valeurs cibles

Average North American: 4–5% Optimal: >8%

Nécessite généralement 2–4 g d'EPA+DHA par jour pour atteindre la cible chez la plupart des gens.

Profondeur mécanistique

EPA and DHA incorporate into cell membrane phospholipids altering fluidity, receptor function, and eicosanoid production. EPA competes with arachidonic acid for COX and LOX enzymes, shifting the balance from pro-inflammatory prostaglandins and leukotrienes toward resolvins and protectins — specialized pro-resolving mediators that actively terminate inflammation rather than just suppressing it.

Interactions clés

  • FADS1/FADS2 variants reduce ALA to EPA/DHA conversion — direct supplementation essential
  • High omega-6 intake competes with omega-3 incorporation
  • Triglyceride form (fish oil) vs ethyl ester affects absorption — triglyceride form superior
  • Vitamin E protects EPA/DHA from peroxidation during supplementation

Personnalisation génomique

La génétique ne détermine pas le destin — mais elle détermine votre terrain biochimique personnel. Ces variantes expliquent pourquoi deux personnes avec des modes de vie identiques peuvent avoir des résultats métaboliques et cardiovasculaires complètement différents.

Variantes clés — à interpréter avec les données génomiques
MTHFR
Le gène le plus discuté en santé fonctionnelle — les variantes ici affectent la façon dont votre corps traite le folate, impactant la méthylation, l'homocystéine et le risque cardiovasculaire.
Methylenetetrahydrofolate reductase — catalyzes conversion of 5,10-MTHF to 5-MTHF, the primary methyl donor for homocysteine remethylation. C677T and A1298C variants reduce enzyme activity 30-70%.
Génomique +

Pourquoi c'est important

MTHFR variants are present in roughly 40% of the population in some form. C677T homozygous (TT genotype) reduces enzyme activity by ~70%, impairing the conversion of dietary folate to the active 5-MTHF form. This raises homocysteine, impairs DNA methylation, reduces SAM availability, and changes the correct form of folate supplementation entirely — folic acid can be counterproductive in these patients.

Action clinique

  • C677T heterozygous (CT): moderate impact, monitor homocysteine
  • C677T homozygous (TT): significant — use 5-MTHF not folic acid
  • A1298C: affects BH4 synthesis, impacts neurotransmitters
  • Check homocysteine, B12, RBC folate alongside genotype

Profondeur mécanistique

5-MTHF is the methyl donor for the MTHFR-driven remethylation of homocysteine to methionine via methionine synthase (MTR). Reduced 5-MTHF availability impairs this reaction, accumulating homocysteine and depleting SAM — the universal methyl donor. SAM depletion impairs DNMT activity (epigenetic methylation), COMT (catecholamine clearance), PNMT (adrenaline synthesis), and dozens of other methyltransferases simultaneously.

Implications pour la supplémentation

  • Use L-5-MTHF (methylfolate) not folic acid for TT genotype
  • Introduce methylfolate slowly — overstimulation common in COMT variants
  • TMG provides BHMT-pathway backup for homocysteine remethylation
  • Riboflavin (B2) is MTHFR cofactor — often deficient alongside
APOE
Le gène de risque cardiovasculaire et Alzheimer le plus important — les porteurs d'APOE4 ont besoin de cibles alimentaires et lipidiques fondamentalement différentes.
Apolipoprotein E — determines lipid particle clearance efficiency via hepatic LDL receptor binding. ε2/ε3/ε4 alleles confer dramatically different cardiovascular and neurodegenerative risk profiles.
Génomique +

Pourquoi c'est important

APOE4 carriers (roughly 25% of the population) have impaired clearance of ApoB-containing lipid particles and dramatically elevated Alzheimer's risk — APOE4 homozygotes have 8-12x elevated Alzheimer's risk vs APOE3. Dietary saturated fat raises LDL far more in APOE4 carriers. Statin targets should be pushed lower. This single gene changes clinical management more than almost any other variant.

Action clinique par génotype

  • ε3/ε3 (most common): standard targets apply
  • ε3/ε4: lower ApoB target (<70), limit saturated fat
  • ε4/ε4: aggressive ApoB target (<60), Mediterranean diet, omega-3 priority
  • ε2/ε3: lowest cardiovascular risk, but watch for dysbetalipoproteinemia

Profondeur mécanistique

APOE protein mediates hepatic uptake of IDL and chylomicron remnants via LDL receptor and LRP1 binding. APOE4 has reduced receptor binding affinity relative to APOE3, impairing remnant clearance and prolonging atherogenic particle plasma residence time. In the brain APOE4 impairs amyloid-β clearance, promotes tau phosphorylation, and disrupts synaptic lipid transport — explaining its neurodegenerative effects.

Implications supplémentation et alimentation

  • APOE4: reduce saturated fat, prioritize olive oil and omega-3
  • APOE4: DHA prioritization for brain protection (high-dose fish oil)
  • APOE4: berberine may improve LDL receptor upregulation
  • APOE2: paradoxically may need different lipid monitoring — watch triglycerides
COMT
Contrôle la rapidité avec laquelle votre corps élimine les hormones de stress et l'œstrogène — les variantes ici affectent directement votre réponse aux suppléments méthylés et votre tolérance au stress.
Catechol-O-methyltransferase — degrades catecholamines (dopamine, norepinephrine, epinephrine) and catechol estrogens via SAM-dependent methylation. Val158Met variant reduces enzyme activity ~40%.
Génomique +

Pourquoi c'est important

COMT is directly relevant to supplement strategy — slow COMT variants (Met/Met) are highly sensitive to methylated supplements. Too much methylfolate or methylcobalamin can flood the methylation system, raise SAM, overstimulate COMT, and produce symptoms of catecholamine excess (anxiety, insomnia, irritability). This is precisely why some patients feel terrible on standard methylation supplements.

Action clinique

  • Val/Val (fast COMT): tolerates methyl donors well, may need more
  • Val/Met (intermediate): start low with methyl donors, titrate slowly
  • Met/Met (slow COMT): high sensitivity — micro-dose methylfolate only
  • Magnesium is COMT cofactor — address deficiency first

Profondeur mécanistique

COMT transfers a methyl group from SAM to catechol hydroxyl groups, producing methoxylated metabolites for urinary excretion. Val158Met substitution reduces thermostability and Vmax by ~40%. Slow COMT means catecholamines clear more slowly — higher prefrontal dopamine tone (better working memory, but anxiety-prone under stress), slower estrogen detoxification (raising 4-OH estrogen quinone risk), and greater sensitivity to SAM fluctuations from supplementation.

Implications pour la supplémentation

  • Met/Met: start methylfolate at 100-200 mcg not 1mg+ doses
  • Hydroxocobalamin or adenosylcobalamin preferred over methylcobalamin
  • Phosphatidylcholine provides methylation support without methyl donor load
  • EGCG (green tea) inhibits COMT — caution in Met/Met genotype
VDR
Votre gène récepteur de la vitamine D — détermine à quel point votre corps répond réellement à la vitamine D, expliquant pourquoi les doses standard fonctionnent pour certains et pas pour d'autres.
Vitamin D receptor — nuclear receptor mediating genomic effects of 1,25(OH)2D3 across 35+ tissues. Bsm1, Fok1, Taq1, and Cdx2 polymorphisms alter receptor expression and ligand sensitivity.
Génomique +

Pourquoi c'est important

Two patients can have identical serum 25-OH vitamin D levels but completely different tissue responses based on VDR genotype. VDR variants explain why some people maintain optimal levels on 1000 IU daily while others need 5000+ IU to see the same response. It personalizes vitamin D dosing from a guess to a targeted strategy — which matters particularly in northern latitudes where baseline deficiency is nearly universal.

Action clinique

  • Fok1 ff genotype: reduced receptor efficiency — higher doses often needed
  • Bsm1 bb: associated with lower bone density response to D3
  • Test serum 25-OH D3 alongside VDR to calibrate individual dose
  • Always pair D3 with K2 (MK-7) and magnesium regardless of genotype

Profondeur mécanistique

VDR forms a heterodimer with RXR upon 1,25(OH)2D3 binding, translocating to the nucleus and binding vitamin D response elements (VDREs) in promoter regions of target genes. Fok1 polymorphism affects the translation start site, producing a receptor 3 amino acids longer with reduced transcriptional efficiency. Bsm1 affects mRNA stability. These functional differences alter the serum-to-tissue response ratio, making genotyping essential for precise supplementation.

Implications pour la supplémentation

  • VDR Fok1 ff: target higher serum 25-OH D3 (125-150 nmol/L)
  • Magnesium deficiency blunts VDR signaling independently of genotype
  • K2 MK-7 (not MK-4) preferred for carboxylation of osteocalcin and MGP
  • Retest 25-OH D3 every 6 months to confirm dose adequacy