Abstract Background It has been shown that increased serum PON1 levels are protective against several disorders. Several single nucleotide polymorphisms (SNPs) of the PON1 gene have been reported to be associated with serum enzyme protein levels and activity. Objective To investigate the association of SNPs of PON1 and serum paraoxonase activity with coronary artery disease (CAD). Methods A total of 601 unrelated patients who underwent coronary angiography including those who had >50% stenosis (N=266) and those with