Genetic determinants of cardiovascular disease risk in familial hypercholesterolemia

Objective-To investigate the contribution of polymorphisms in multiple candidate genes to cardiovascular disease (CVD) risk in a large cohort of patients with heterozygous familial hypercholesterolemia (FH). Methods and Results-We genotyped 1940 FH patients for 65 polymorphisms in 36 candidate genes. During 91.451 person-years, 643 (33.1%) patients had at least 1 cardiovascular event. Multifactorial Cox survival analysis revealed that the G20210A polymorphism in the prothrombin gene was strongly associated with a significantly increased CVD risk (GA versus GG; P <0.001). Conclusions-In a large cohort of FH patients, we found that the G20210A polymorphism in the prothrombin gene is strongly associated with CVD risk. Our results constitute a step forward in the unraveling of the hereditary propensity toward CVD in FH and might lead to better risk stratification and hence to more tailored therapy for CVD preventio

Genetic determinants of plasma HDL-cholesterol levels in familial hypercholesterolemia

The objective of this study was to determine the extent to which common genetic variants can explain the variation of high-density lipoprotein cholesterol (HDL-C) plasma levels in familial hypercholesterolemia (FH). FH is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease (CVD). Although low HDL-C levels have been shown to affect the severity of the clinical phenotype, little is known about the factors that determine HDL-C levels in these patients. A cohort of 1002 heterozygous FH patients was genotyped for polymorphisms in the genes encoding for ATP-binding cassette transporter A1, apolipoprotein (apo) AIV, apoCIII, apoE, cholesteryl transfer ester protein, hepatic lipase, lipoprotein lipase, and two paraoxonases. Multiple linear regression showed that, together, these polymorphisms explain only 3.9% of the variation of HDL-C plasma levels. When significant two-way interactions between the polymorphisms were also taken into account, the explained variation rose to 12.5%. In a regression model that also incorporated sex, smoking, alcohol use, body mass index, and concomitant beta-blocker use as covariates, the explained variation of HDL-C plasma levels even increased to 32.5%. This study provides direct evidence that multiple, modestly penetrant, but highly prevalent, polymorphisms can explain a substantial part of the variation of HDL-C plasma levels in a representative large cohort of heterozygous FH patient

Comprehensive CYP2D6 genotype and adherence affect outcome in breast cancer patients treated with tamoxifen monotherapy

International audienceThe association between genotype and outcome in breast cancer patients treated with adjuvant tamoxifen remains controversial. We assessed the influence of comprehensive versus limited genotype in the context of tamoxifen adherence and co-medication in a large cohort of 618 patients. Genotyping of 33 alleles used two archival cohorts from tamoxifen-treated women with invasive breast cancer (Dundee,  = 391; Manchester,  = 227). Estimates for recurrence-free survival (RFS) were calculated based on inferred CYP2D6 phenotypes using Kaplan–Meier and Cox proportional hazard models, adjusted for nodal status and tumour size. Patients with at least one reduced function allele (60%) or no functional alleles (6%) had a non-significant trend for worse RFS: hazard ratio (HR) 1.52 (CI 0.98–2.36,  = 0.06). For post-menopausal women on tamoxifen monotherapy, the HR for recurrence in patients with reduced functional alleles was 1.96 (CI 1.05–3.66,  = 0.036). However, RFS analysis limited to four common allelic variants was no longer significant ( = 0.39). The effect of genotype was increased by adjusting for adherence to tamoxifen therapy, but not significantly changed when adjusted for co-administration of potent inhibitors of CYP2D6. Comprehensive genotyping of and adherence to tamoxifen therapy may be useful to identify breast cancer patients most likely to benefit from adjuvant tamoxifen