Association between Polymorphisms in Toll-like Receptor 9 Gene and Outcomes after Ischemic Stroke

ABSTRACT

Several evidences suggested that Toll-like receptor 9 (TLR9) plays an important role in atherosclerosis and neuroprotection but the association between the TLR9 and risk for stroke or outcomes after stroke has not been investigated. The aim of the present study was to investigate the association between TLR9 polymorphisms and the risk for ischemic stroke using a case-control study design. We also explored the correlation between the polymorphisms and outcomes after stroke. We enrolled consecutive Korean stroke patients and controls without history of stroke. Four polymorphisms, namely c.-1486T>C, c.-1237C>T, c.1174A>G, and c.2848G>A were examined using polymerase chain reaction followed by direct sequencing. Initially we examined 193 stroke patients and the same number of healthy adults who had no history of stroke as controls. Due to deviation from Hardy-Weinberg equilibrium of initial controls, we performed genetic analysis of two polymorphisms (c.1174A>G and c.2848G>A) for additional 165 controls. The genotype frequency of four polymorphisms did not differ significantly between stroke patients and controls in unadjusted analysis. The variant allele (C) in c.-1486 locus was associated with significantly increased chance of favorable functional outcome at three month after stroke (OR 2.32, 95% CI 1.02~5.26, p = 0.043).