The ClC-KbT481S chloride channel gene polymorphism, ischaemic stroke and hypertension

Stroke is a polygenic disorder. Previous genetic studies focused on candidate genes influencing pathogenic processes, with little emphasis on genes influencing vascular risk factors. Previous research linked the ClC-Kb T481S poly- morphism to blood pressure (BP). We therefore undertook an association study to determine the relevance of this poly- morphism to stroke, particularly lacunar stroke, given its strong correlation with hypertension. We genotyped DNA from 180 patients with acute ischaemic stroke (44 having lacunar stroke) and 298 age- and gender-matched controls using a se- quence-specific polymerase chain reaction method (SS-PCR). We found no association between the ClC-Kb T481S poly- morphism and ischaemic stroke (Odds Ratio (OR): 0.87, 95% Confidence Interval (CI): 0.57-1.33). Stratification for stroke subtype did not alter this finding. This polymorphism showed a borderline association with history of hypertension (p=0.06) but was not associated with systolic or diastolic BP (p>0.05). To our knowledge there are no other studies pub- lished on this polymorphism and stroke.