Background: Paraoxonases (PONs) are a family of orphan enzymes with multiple functions, including anti-inflammatory, antioxidative, antiatherogenic activities. Studies have suggested that genetic variations in PON1  and PON2  are associated with ischemic stroke (IS) risk; however, the conclusion remains unclear in the Chinese population.
Methods: To investigate the susceptibility of genetic variations in PON1  and PON2  to risk of IS and its subtypes, this case–control study was carried out on a Chinese population comprising 300 IS patients and 300 healthy controls. Genotypes of six genetic variations in PON1  and PON2  were identified with an improved multiplex ligase detection–reaction technique.
Results: PON1  rs662 was associated with increased risk of IS (CT vs. TT — OR_adjusted 1.79, 95% CI 1.08– 2.97; p =0.025). Stratified analysis for patients by sex revealed that the significant association of PON1  rs662 with IS risk was maintained in the male cohort (CT vs. TT — OR_adjusted 2.59, 95% CI 1.29– 5.21 [p =0.009]; CT/CC vs. TT — OR_adjusted 2.03, 95% CI 1.05– 3.93 [p =0.036]), but not in the female cohort. Analysis according to IS subtype revealed that PON1  rs662 genetic variation was an increased risk in the subcohort of patients with large-artery atherosclerosis (CT/CC vs. TT — OR_adjusted 2.31, 95% CI 1.09– 4.91; p =0.029), but not in patients with other types of IS.
Conclusion: This study suggested that PON1  rs662 presented a potential risk of IS, especially for males, and this association was more obvious for large-artery atherosclerosis.
Keywords: ischemic stroke, genetic variation, PON1 , PON2