rs4149584 — TNFRSF1A R92Q

TNFRSF1A R92Q — The TNF Receptor Variant That Bridges Periodic Fever and MS

The TNFRSF1A gene encodes TNF receptor 1 (TNFR1), the primary signaling receptor for tumor necrosis factor-alpha (TNF-α), a master inflammatory cytokine expressed on virtually every nucleated cell in the body. When TNF-α binds TNFR1, it can trigger cell death, inflammation, immune activation, or in certain tissue contexts, tissue repair — making the receptor's tight regulation essential. The R92Q variant (rs4149584) substitutes glutamine for arginine at position 92 of the mature protein, altering how the receptor binds TNF-α and how it traffics through the cell. The consequence is a SNP with two distinct clinical faces: a rare but recognized autoinflammatory disorder called TRAPS¹¹ TRAPS
TNF Receptor-Associated Periodic Syndrome — characterized by recurrent, self-limiting episodes of fever, serositis, rash, and musculoskeletal pain lasting days to weeks at one end, and a modest but independently established risk for multiple sclerosis at the other.

The Mechanism

Arginine at position 92 sits in the cysteine-rich domain (CRD1) of TNFR1's extracellular region — not at the TNF-α binding interface directly, but within a domain important for receptor folding and trafficking. Molecular dynamics simulations²² Molecular dynamics simulations
Agulló et al. (2015) modeled the R92Q variant and found the mutation substantially reshapes the receptor-ligand interaction geometry show that the R92Q substitution expands the contact area between TNFR1 and TNF-α from 1,070 Ų to 1,388 Ų, tightening the interaction and reducing the receptor-ligand distance from 28.7 to 27.9 Å. At the same time, in cell-based transfection experiments, R92Q protein fails to reach the plasma membrane³³ R92Q protein fails to reach the plasma membrane
Gomez-Pinedo et al. (2022) showed R92Q protein accumulates in the endoplasmic reticulum of oligodendroglioma cells rather than trafficking to the cell surface efficiently — it accumulates in the endoplasmic reticulum (ER) instead of being delivered to the cell surface. This ER retention has two consequences: first, it reduces cell-surface TNFR1 signaling capacity; second, it may activate the unfolded protein response, a pathway that itself drives inflammation. The net effect in carriers appears to be paradoxically elevated soluble TNF-R1 in serum — Comabella et al. found⁴⁴ Comabella et al. found
Comabella et al. Neurology 2013 measured sTNF-R1 in 2,032 MS patients; R92Q carriers had significantly higher circulating sTNF-R1 (p=0.003) and elevated full-length TNFRSF1A mRNA (p=0.011) significantly higher circulating sTNF-R1 levels in R92Q carriers (p=0.003), along with upregulated TNFRSF1A mRNA. Increased caspase-3 (CASP3) mRNA expression in R92Q carriers suggests heightened apoptotic signaling downstream of the receptor.

TRAPS: Recurrent Fever From a Leaky Immune Brake

TRAPS was first described as a dominant disorder caused by rare, high-penetrance mutations in TNFRSF1A — particularly those disrupting cysteine residues in the extracellular domain, which severely misshape the receptor. R92Q sits in a distinct mechanistic category: a low-penetrance TRAPS variant⁵⁵ low-penetrance TRAPS variant
ClinVar classifies R92Q as "conflicting classifications" — 9 submissions call it benign, 7 call it uncertain significance, reflecting its low penetrance and variable expressivity across families with incomplete penetrance, variable expressivity, and a much milder phenotype than classic TRAPS. When R92Q does cause autoinflammatory symptoms, carriers experience episodic fever lasting days to weeks, arthralgias, myalgias, urticarial skin rash, and severe fatigue — clinically indistinguishable from classic TRAPS but milder and typically adult-onset rather than childhood-onset. Kümpfel et al. (2008)⁶⁶ Kümpfel et al. (2008)
Kümpfel et al. Neurology 2008 — 21 MS patients with R92Q, all showing TRAPS-compatible symptoms; clinical severity was milder than typical TRAPS found that among 21 MS patients carrying R92Q, all exhibited TRAPS-compatible symptoms — mainly myalgias, arthralgias, headache, severe fatigue, and skin rashes. A dose-effect study⁷⁷ dose-effect study
Grandemange et al. Mol Genet Genomic Med 2017 — first documentation of R92Q homozygosity producing more severe TRAPS-like phenotype than heterozygosity found that homozygous R92Q individuals show more severe autoinflammatory presentations than heterozygotes, suggesting the variant's autoinflammatory effects are dosage-sensitive.

The Evidence for MS Risk

R92Q emerged from multiple genome-wide and candidate-gene association studies as an independent MS susceptibility variant. A GWAS meta-analysis⁸⁸ GWAS meta-analysis
Caminero et al. Clin Exp Immunol 2011 — aggregated GWAS data identifying R92Q as MS risk factor with OR=1.6 assigned an odds ratio of 1.6 for MS. A Belgian replication study — 967 MS patients versus 1,022 controls⁹⁹ 967 MS patients versus 1,022 controls
Goris et al. J Neuroimmunol 2011 (p=5×10⁻⁴), finding R92Q in 3% of MS patients vs 1% of controls — found the variant in 3% of MS cases versus 1% of controls, yielding OR=2.26 (95% CI 1.41–3.61), and confirmed this association was independent of the common splice-region variant rs1800693 in the same gene. The two variants are not in strong linkage disequilibrium (r²≈0.041 in Europeans) and represent mechanistically distinct signals. Comabella et al.¹⁰¹⁰ Comabella et al.
Comabella et al. Neurology 2013 — 2,032 MS patients, showing R92Q carriers had younger disease onset and slower progression found R92Q carriers had younger age at MS onset and, notably, slower disease progression compared to non-carriers — suggesting the variant may influence disease trajectory as well as susceptibility. The pediatric MS literature adds further weight: Blaschek et al. (2018)¹¹¹¹ Blaschek et al. (2018)
Blaschek et al. Eur J Paediatr Neurol 2018 — 29 pediatric MS patients, R92Q detected in 6/11 mutation-positive cases; SMR 4.6–13.6 depending on reference population found R92Q in 6 of 29 childhood-onset MS patients with a standardized morbidity ratio of 4.6–13.6 relative to expected population frequency.

Practical Actions

For most carriers, the MS risk contribution from a single T allele is modest (OR~1.6–2.3) and does not require clinical intervention beyond awareness. However, carriers who also develop unexplained episodic fever, joint pain, or rash should raise the possibility of low-penetrance TRAPS with their physician — the diagnosis changes management meaningfully. Colchicine is often effective for TRAPS symptom control in mild cases, while anti-IL-1 biologics (anakinra, canakinumab) are used for refractory cases. Critically, standard anti-TNF biologics used in rheumatology (infliximab, adalimumab, etanercept) are generally contraindicated in TRAPS — they can paradoxically worsen autoinflammatory flares, and in any TNFRSF1A variant carrier, they carry elevated neurological risk. Homozygous TT carriers (extremely rare, ~0.01% of the population) have a meaningfully elevated risk of both autoinflammatory disease and MS and warrant referral to an autoinflammatory specialist regardless of current symptoms.

Interactions

R92Q (rs4149584) and the splice-region variant rs1800693 in the same gene are mechanistically independent signals. rs1800693 generates a soluble Δ6-TNFR1 decoy isoform that sequesters TNF-α; R92Q generates a full-length receptor with tighter TNF-α binding but impaired cell-surface trafficking. The two mechanisms could theoretically combine: one reducing membrane receptor density (R92Q via ER retention), the other generating a competing soluble decoy (rs1800693 Δ6 isoform). Compound carriers of both risk alleles have not been formally studied for MS risk but are expected to carry additive susceptibility from independent mechanisms. Clinicians should consider both variants when evaluating TNFRSF1A-related disease risk.