Scientists Map the Immune Genes That Drive Aging at Single-Cell Resolution

Aging is not a single process but a tapestry of interacting genetic and immune mechanisms that remain poorly understood at the cellular level. Knowing which genes, in which immune cells, causally accelerate biological aging is essential for developing targeted, safe therapies—yet that resolution has been largely missing from prior research.

This study addressed that gap by integrating single-cell expression quantitative trait loci (sc-eQTL) data with Mendelian randomization (MR) and colocalization analyses. The team evaluated 8,733 eGenes across 14 distinct immune cell types, testing each for causal effects on three validated aging proxies: telomere length, facial aging score, and frailty index. Colocalization required a posterior probability above 50% for a shared causal variant (PP.H4), adding a stringent filter against false positives.

The analysis yielded 27 immune-cell-specific eGenes with strong causal and colocalization evidence. Standout regulators included FUBP1 (linked to DNA stability), TUFM (mitochondrial translation), ATIC (purine biosynthesis), and SLC22A5 (carnitine transport), each showing distinct effects depending on cell type and aging trait examined. This cell-type specificity is a key advance over bulk-tissue approaches.

PheWAS screening found minimal off-target disease associations for most identified genes, supporting their viability as therapeutic targets with manageable safety profiles. Drug-repurposing analysis then matched these targets to approved or investigational compounds—including Irofulven, zinc-based agents, and acetylcarnitine—that could feasibly be redirected toward aging-related indications.

The framework is scalable and reproducible, but key caveats apply. Findings derive from genetic proxies of gene expression rather than direct intervention, and causal claims depend on MR assumptions that may not fully hold. Clinical translation will require validation in functional models and prospective trials.