Examining the link between 179 lipid species and 7 diseases using genetic predictors

Area of Science:

• Cardiovascular Genetics
• Metabolomics
• Disease Risk Prediction

Background:

• Genome-wide association studies (GWAS) link lipid species loci to diseases, but causal relationships are unclear.
• Understanding plasma lipid species' role in disease etiology is crucial for public health.

Purpose of the Study:

• To investigate the causal impact of plasma lipid species on the risk of seven major diseases.
• To leverage genetic predictors for lipid species to elucidate disease associations.

Main Methods:

• Developed genetic predictors for 179 lipid species using genomic loci and polygenic scores (PGS) in Finnish individuals.
• Conducted disease association analyses across three large cohorts (FinnGen, UK Biobank, Generation Scotland).
• Employed univariable and multivariable Mendelian randomization (MR) to assess independent effects of lipid species on disease risk.

Main Results:

• Polygenic scores explained over 4% of variance for 34 lipid species; high-impact loci variants associated with all seven diseases.
• Multivariable MR (MVMR) confirmed apolipoprotein B (ApoB) as causally linked to ischemic heart disease.
• Specific phosphatidylethanolamine variants showed a protective effect against age-related macular degeneration, independent of HDL-cholesterol.
• MVMR indicated a protective role for four arachidonic acid-containing lipids in cholelithiasis risk, independent of total cholesterol.

Conclusions:

• Genetic predictors of lipid species offer valuable insights into disease risk mechanisms.
• Identified potential causal links between lipid species and age-related macular degeneration and cholelithiasis.
• Findings suggest novel targets for disease risk prediction and therapeutic interventions.