rs3750243 — EIF4EBP1 EIF4EBP1 mTOR Pathway Variant

EIF4EBP1 — The mTOR Gatekeeper Controlling How Quickly Your Ovaries Age

Inside every ovary sits a dormant population of primordial follicles — the finite reserve of egg precursors you are born with. How quickly this pool depletes determines when your fertility naturally declines and when menopause arrives. One of the most important molecular gatekeepers of this process is 4E-BP1¹¹ 4E-BP1
eukaryotic translation initiation factor 4E-binding protein 1; encoded by EIF4EBP1 on chromosome 8p11.23; a direct downstream effector of mTORC1 that, when unphosphorylated, inhibits cap-dependent protein synthesis and suppresses cell proliferation and growth. When mTOR activity is low, 4E-BP1 remains active and keeps primordial follicles quiescent. When mTOR is highly active, 4E-BP1 is phosphorylated and inactivated — follicles start waking up and the reserve depletes faster.

The rs3750243 variant sits approximately 2 kilobases upstream of EIF4EBP1 in a regulatory region. The C allele at this position is associated with later age at menopause and higher anti-Müllerian hormone (AMH) levels — two direct measures of ovarian reserve — suggesting it acts on EIF4EBP1 expression or activity in a way that keeps the mTOR brake engaged for longer.

The Mechanism

mTOR (mechanistic target of rapamycin) integrates nutrient, energy, and growth-factor signals to decide whether a cell should grow, divide, or remain quiescent. In primordial follicles, the PI3K–Akt–mTORC1 axis²² PI3K–Akt–mTORC1 axis
phosphoinositide 3-kinase activates Akt, which phosphorylates and activates mTORC1; mTORC1 then phosphorylates S6K1 and 4E-BP1, promoting cell growth and proliferation; excessive mTORC1 activation in oocytes accelerates follicle recruitment beyond the sustainable rate is one of the principal determinants of follicle activation rate.

4E-BP1 sits directly downstream of mTORC1. In its unphosphorylated (active) form, it binds eIF4E and blocks cap-dependent mRNA translation — effectively slowing cell growth and keeping follicles dormant. mTORC1 phosphorylates 4E-BP1 at multiple residues, releasing eIF4E and allowing translation to proceed, which promotes follicle activation. The regulatory variant rs3750243 upstream of EIF4EBP1 is hypothesised to influence how readily this brake can be applied: the C allele may sustain higher baseline 4E-BP1 expression or activity, tipping the balance toward follicle quiescence.

The animal-model evidence for mTOR as an ovarian-reserve regulator is strong. Zhang et al. 2013³³ Zhang et al. 2013
Rapamycin preserves the follicle pool reserve and prolongs the ovarian lifespan of female rats. Eur J Obstet Gynecol Reprod Biol, PMID 23566837 showed that rapamycin (the prototypic mTOR inhibitor) administered every other day for 10 weeks doubled the primordial follicle count in rat ovaries relative to controls (p<0.001), with corresponding decreases in phospho-mTOR and phospho-p70S6K and increases in the longevity regulators SIRT1 and SIRT6. A separate study by Chen et al. 2022⁴⁴ Chen et al. 2022
Rapamycin maintains the primordial follicle pool and protects against chemotherapy-induced damage, PMID 35718464 confirmed that rapamycin inhibited excessive follicle activation and reduced apoptosis in mice exposed to chemotherapy.

The Evidence

rs3750243 emerged as one of the strongest signals in the landmark Ruth et al. 2021 Nature GWAS⁵⁵ Ruth et al. 2021 Nature GWAS
Genetic insights into biological mechanisms governing human ovarian ageing; 201,323 European-ancestry women; 290 independent signals at genome-wide significance; PMID 34349265 — a study of 201,323 European-ancestry women powered to detect even modest genetic effects on age at menopause. The EIF4EBP1 locus at 8p11.23 showed an exceptional p-value of 5×10⁻²⁶¹ with a beta of +0.376 years per C allele. This means each copy of the C allele is associated with roughly 4.5 additional months of reproductive lifespan — and women who are CC homozygous carry approximately 9 months' advantage over GG homozygotes on average.

The same genomic region influences the most clinically actionable biomarker of ovarian reserve. Pujol-Gualdo et al. 2024 Human Reproduction⁶⁶ Pujol-Gualdo et al. 2024 Human Reproduction
GWAS meta-analysis of AMH in 9,668 pre-menopausal women; three novel AMH loci including EIF4EBP1; PMID 38815977 identified EIF4EBP1 as one of three novel genome-wide significant AMH loci, meaning that variants in this region measurably alter circulating anti-Müllerian hormone — the glycoprotein secreted by small antral follicles that is used clinically to estimate the remaining follicle pool. The association was further replicated by Erdogan-Yildirim et al. 2025 Genes⁷⁷ Erdogan-Yildirim et al. 2025 Genes
AMH GWAS in 1,185 Samoan women; replication of EIF4EBP1 AMH locus; PMID 40725450 across an independent non-European cohort, establishing cross-ancestry relevance.

EIF4EBP1's position as a direct mTOR effector gives this locus a compelling mechanistic interpretation. Unlike many GWAS hits that tag unknown regulatory elements near genes of uncertain relevance, 4E-BP1 has a well-characterised role in the exact pathway (mTOR) that animal models have repeatedly shown governs primordial follicle activation rate.

Practical Actions

For women who carry the GG genotype — the most common configuration — the practical implication is awareness: mTOR pathway activity is a meaningful lever on ovarian ageing, and interventions that support the 4E-BP1 brake (mTOR modulation) may have particular relevance. Caloric restriction, time-restricted eating, and CoQ10 supplementation all have mechanistic connections to mTOR activity and mitochondrial function in the ovary.

AMH testing provides a direct window into how this genetic variant is expressing itself in your specific physiology. A single fasting AMH level at any point in the cycle gives a reasonable estimate of remaining follicle pool; trajectories (measured 12–18 months apart) are more informative than a single value.

Interactions

The EIF4EBP1 rs3750243 locus sits in the same mTOR pathway context as other longevity-related mTOR variants. rs2295080 in MTOR itself (the kinase that phosphorylates 4E-BP1) and rs3803304 in PIK3CA (the upstream PI3K activating Akt and mTOR) both influence pathway activity from upstream nodes. The combined picture of rs3750243 (the brake, 4E-BP1) plus upstream mTOR or PI3K variants may determine the net mTOR activity level in ovarian tissue more precisely than any single variant. No compound effect sizes have been published for this combination.

rs2268361 in FSHR (follicle-stimulating hormone receptor) sits at a mechanistically adjacent node: FSH signalling through FSHR activates the same PI3K cascade that feeds into mTOR. FSHR variants affecting receptor sensitivity interact with the mTOR pathway at the point of signal input, while EIF4EBP1 variants affect signal output. The two loci likely modulate ovarian reserve through overlapping but distinct mechanisms.