OBJECTIVES: A significant inter-individual variability in statin treatment efficacy is likely to have a strong genetic background. A candidate gene with the potential to influence statin treatment efficacy is SLCO1B1. This gene codes for the solute carrier organic anion transporter, which has been shown to regulate the hepatic uptake of statins and some other drugs.
MATERIALS AND METHODS: The SLCO1B1 rs4149056 (T>C) polymorphism was successfully analysed in a group of 253 patients with dyslipidemia (treated with simvastin or atorvastatin, 10 or 20 mg per day) and 470 healthy normolipidemic controls. The polymorphism was analysed using nested PCR-RFLP. Lipid levels (total, LDL and HDL cholesterol; triglycerides) were analysed before and after 10-13 weeks of treatment.
RESULTS: After treatment, as expected, there was a significant decrease both in the total cholesterol (7.60±1.36 → 5.37±1.12 mmol/L, p<0.001) and LDL cholesterol (5.04±1.34 → 3.17±0.99 mmol/L, p<0.001) levels. The distribution of the individual genotypes in the patients (TT=61.7%, CT=31.6%, CC=6.7%) was similar (p=0.35) to that of the normolipidemic controls (TT=64.4%, CT=31.3%, CC=4.3%). Homozygous CC males exhibited the lowest (Δ -21.2±7.2%) decrease of total cholesterol in contrast to the females, in whom the same genotype was associated with the highest (Δ -33.5±7.6 %) decrease (p=0.04 for gene-gender interaction).
CONCLUSIONS: The results of our pilot study suggest possible gender-dependent effects of the rs4149056 variant within the SLCO1B1 gene on statin treatment efficacy.