rs114280794 (TMEM108): AMD and VLDL Lipid Research
Key takeaways
- rs114280794 near TMEM108 has been studied for links to age-related macular degeneration (AMD) through blood lipid pathways.
- A UK Biobank study of 72,376 people found 84 blood metabolite markers associated with AMD, with lipoprotein subclasses the most common category at 39%.
- Mendelian randomization found that depletion of very small VLDL particles in blood is likely a direct cause of AMD, not just a statistical correlation.
- Age is the dominant AMD risk factor; blood lipid markers add a smaller but measurable contribution to risk models.
- Evidence is from a single cohort and should be considered preliminary until independently replicated.
Key takeaways
- rs114280794, located near the TMEM108 (Transmembrane Protein 108) gene, has been investigated in connection with age-related macular degeneration (AMD) and blood lipid particles.
- A UK Biobank study of 72,376 people found 84 blood metabolite markers significantly associated with AMD, with lipoprotein (fat-carrying blood particle) subclasses making up the largest category at 39% of associated markers.
- Mendelian randomization analysis found that depletion of very small VLDL (very low-density lipoprotein) blood fat particles is likely a direct cause of AMD, not just a correlation.
- Age is the dominant risk factor for AMD in this research; blood lipid markers contribute a measurable but smaller share to risk prediction.
- Evidence is preliminary and comes from a single cohort study without independent replication reported.
What the research says A study of UK Biobank donors (n=72,376; 1,353 AMD cases and 71,023 controls) examined 325 blood metabolites for association with AMD and found 84 significantly associated markers after false discovery rate (FDR) correction, a statistical adjustment used to limit false positives when testing many variables simultaneously. Lipoprotein subclasses accounted for approximately 39% of these AMD-associated metabolites, with several lipoprotein-to-lipid ratios also represented. Applying Mendelian randomization (a method that uses genetic variants as proxies to test whether a metabolite causally affects a disease rather than simply correlating with it) across 98,316 European participants, the authors identified 19 metabolites as likely having a causal role in AMD; six of these were components of very small VLDL particles and one was the phospholipid-to-total-lipid ratio in medium VLDL, leading the authors to conclude that depletion of circulating very small VLDLs is likely causal for AMD.
Reported associations
- Age-related macular degeneration (AMD): A genome-wide metabolite association study in UK Biobank found 84 blood metabolite markers significantly associated with AMD at FDR-adjusted p < 0.05, with lipoprotein subclasses as the most prevalent category (39% of associated markers; n=72,376).
- Very small VLDL levels and AMD: Two-sample Mendelian randomization identified depletion of circulating very small VLDL particles as likely causal for AMD, based on metabolite GWAS instruments derived from 98,316 European participants from the UK Biobank.
- Blood lipoprotein-to-lipid ratios: Phospholipid-to-total-lipid ratios in medium VLDL were among the 19 metabolites identified by Mendelian randomization as likely causally related to AMD.
Evidence quality The available evidence comes from a single large UK Biobank study (n=72,376 for AMD-metabolite associations; n=98,316 for the metabolite GWAS instruments used in Mendelian randomization). FDR correction was applied across 325 metabolites tested. The use of two-sample Mendelian randomization strengthens causal inference beyond simple correlation, but independent replication in a separate cohort is not described in the available study text. Age was identified as the primary predictive factor in a machine learning risk model, with metabolites including lipoprotein subclasses contributing more modestly. The specific functional role of this locus in the lipoprotein pathways described is not detailed in the available text, and the overall body of evidence should be considered preliminary.
Lifestyle considerations No lifestyle considerations on file for this variant.
Frequently asked questions
What is TMEM108 and what does it do?
TMEM108 stands for Transmembrane Protein 108. The available research on the rs114280794 variant in this region focuses on associations with blood lipid levels and age-related macular degeneration rather than describing the protein's direct cellular function.
Is rs114280794 linked to age-related macular degeneration?
Research in a large UK Biobank study found that blood lipoprotein subclasses, especially very small VLDL particles, are associated with AMD and that this relationship may be causal according to Mendelian randomization analysis. The specific role of this variant within the TMEM108 locus in that pathway is not yet fully established in the available evidence.
What is VLDL and why does it matter for AMD?
VLDL stands for very low-density lipoprotein, a type of fat-carrying particle in the blood. A large study using Mendelian randomization found that lower levels of very small VLDL subclasses appear to increase AMD risk, suggesting these lipid particles may influence the health of retinal tissue.
How strong is the evidence connecting this variant to macular degeneration?
The evidence comes from a single large UK Biobank study (over 72,000 participants) using Mendelian randomization, which provides stronger causal evidence than correlation alone. However, independent replication in a separate cohort has not been reported, so the findings are considered preliminary.
What role do lipids play in AMD risk?
Lipid-rich deposits called drusen are a hallmark feature of early AMD, and abnormal changes in blood lipid profiles have been identified in multiple studies. One large UK Biobank analysis found that lipoprotein subclasses made up 39% of blood metabolites significantly associated with AMD, with very small VLDL depletion identified as a likely causal factor.