A protective role of a cholesteryl ester transfer protein gene variant towards ischaemic stroke in Sardinians

OBJECTIVES: Cholesteryl ester transfer protein (CETP) plays a key role in the metabolism of high-density lipoprotein (HDL), a strong, inverse, independent risk factor for cardiovascular disease. We sought to investigate the relationship between a common variant of CETP gene, the Taq1 B polymorphism, that has been previously associated with CETP blood concentrations, and the risk of ischaemic stroke in a genetically homogenous population from the Sardinia island, Italy. This population has been previously shown to be a highly conservative sample. DESIGN: A total of 215 cases of ischaemic stroke and 236 controls were selected and characterized for the CETP Taq1 B polymorphism. Allele and genotype frequencies were compared amongst cases and controls. RESULTS: Age, hypertension and hypercholesterolaemia were independent risk factors for stroke in this cohort. We found that presence of the CETP Taq1 B2 allele was associated with a significantly decreased risk of ischaemic stroke when assuming a recessive mode of inheritance (OR 0.55, 95% CI = 0.34-0.90, P = 0.017). This result was confirmed by multivariate analysis, after adjustment for age, presence of hypertension and hypercholesterolaemia (OR 0.53, 95% CI = 0.32-0.88, P = 0.014). By performing separate analysis for gender we found that the effect was present in females but not in males, with a significant sex-CETP gene variant interaction for both recessive (P = 0.005) and additive (P = 0.029) modes of inheritance. CONCLUSIONS: Our data suggest that the Taq1 B2 allelic variant of the CETP gene may be associated, as a protective factor, with occurrence of ischaemic stroke. Further studies are needed to further elucidate the clinical implications of our finding.