A polymorphism associated with increased levels of YKL-40 and the risk of early onset of lone atrial fibrillation

Background: Plasma levels of YKL-40 are elevated in patients with atrial fibrillation (AF). We hypothesized that a single nucleotide polymorphism (SNP) that affects YKL-40 plasma levels is associated to the risk of lone AF. Findings: We included 178 young patients with lone AF and the first episode before the age of 40 years, and a control group of 875 healthy individuals. We analyzed a promoter SNP (-131CG) (rs4950928) in the Chitinase 3-like 1 (CHI3L1) gene encoding YKL-40, which had previously been associated with elevated levels of YKL-40. Conclusions: The (-131CG) genotype was not associated with increased risk of AF. Genetically increased YKL-40 levels were not associated to AF.