What is Atrial Fibrillation Risk Single-Nucleotide Polymorphisms?
Genome-wide association studies have identified common single-nucleotide polymorphisms near genes implicated in cardiac ion channel function, structural remodelling, and developmental pathways (notably chromosome 4q25 near PITX2) that are robustly associated with atrial fibrillation risk across populations. These variants modulate susceptibility to AF through effects on atrial electrophysiology, fibrosis, and structural substrate, but environment, comorbidity, and other genetic factors combine to determine phenotype. The genetic architecture of AF is polygenic, so individual SNPs confer modest effect sizes and are aggregated into a risk score.