Putative functional SNPs in SLC22A3 and H3F3B might influence the development of CAD by regulating the lipid levels

A Polynesian-specific SLC22A3 variant associates with low plasma lipoprotein(a) concentrations independent of apo(a) isoform size in males

Lipoprotein(a) (Lp(a)) is a low-density lipoprotein (LDL)-like particle in which the apolipoprotein B component is covalently linked to apolipoprotein(a) (apo(a)). Lp(a) is a well-established independent risk factor for cardiovascular diseases. Plasma Lp(a) concentrations vary enormously between individuals and ethnic groups. Several nucleotide polymorphisms in the SLC22A3 gene associate with Lp(a) concentration in people of different ethnicities. We investigated the association of a Polynesian-specific (Māori and Pacific peoples) SLC22A3 gene coding variant p.Thr44Met) with the plasma concentration of Lp(a) in a cohort of 302 healthy Polynesian males. An apo(a)-size independent assay assessed plasma Lp(a) concentrations; all other lipid and apolipoprotein concentrations were measured using standard laboratory techniques. Quantitative real-time polymerase chain reaction was used to determine apo(a) isoforms. The range of metabolic (HbA1c, blood pressure, and blood lipids) and blood lipid variables were similar between the non-carriers and carriers in age, ethnicity and BMI adjusted models. However, rs8187715 SLC22A3 variant was significantly associated with lower Lp(a) concentrations. Median Lp(a) concentration was 10.60 nmol/L (IQR: 5.40-41.00) in non-carrier group, and was 7.60 nmol/L (IQR: 5.50-12.10) in variant carrier group (P<0.05). Lp(a) concentration inversely correlated with apo(a) isoform size. After correction for apo(a) isoform size, metabolic parameters and ethnicity, the association between the SLC22A3 variant and plasma Lp(a) concentration remained. The present study is the first to identify the association of this gene variant and low plasma Lp(a) concentrations. This provides evidence for better guidance on ethnic specific cut-offs when defining 'elevated' and 'normal' plasma Lp(a) concentrations in clinical applications.

LncRNA RP1-276N6.2 Expression and RP1-276N6.2 Gene Polymorphisms Contribute to the Risk of Coronary Artery Disease in Chinese Han Population

Long noncoding RNAs (lncRNAs) have been implicated in coronary artery disease (CAD) processes. However, the relationship between the gene polymorphisms of lncRNA RP1-276N6.2 as a novel molecule and susceptibility to CAD remains unclear. In our case-control study, 949 CAD patients and 892 healthy controls were genotyped using the TaqMan genotyping assay. The quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay were performed to examine the expression levels of RP1-276N6.2 and SLC22A3(OCT3). We observed that CAD patients had significantly lower RP1-276N6.2 levels than those healthy participants (p < 0.05). Compared to the wild-type genotype, the rs611950 T allele and the rs10499313 AG genotype and G allele significantly increased the premature CAD risk (p = 0.02, p = 0.002, and p = 0.01, respectively), while the rs505000 G allele reduced this risk (p = 0.01); moreover, the rs505000 CG genotype significantly enhanced the delayed CAD risk (p = 0.03), and the rs505000 G allele reduced the expression levels of RP1-276N6.2 and SLC22A3 (p < 0.05 and p < 0.05, respectively). In addition, RP1-276N6.2 positively regulated the mRNA and secreted protein levels of SLC22A3 (p < 0.05). In conclusion, the RP1-276N6.2 gene polymorphisms were closely associated with CAD risk. LncRNA RP1-276N6.2 may be a potential genetic target for CAD early diagnosis and treatment.

Genetic, Molecular, and Cellular Determinants of Sex-Specific Cardiovascular Traits

Despite the well-known sex dimorphism in cardiovascular disease traits, the exact genetic, molecular, and cellular underpinnings of these differences are not well understood. A growing body of evidence currently points at the links between cardiovascular disease traits and the genome, epigenome, transcriptome, and metabolome. However, the sex-specific differences in these links remain largely unstudied due to challenges in bioinformatic methods, inadequate statistical power, analytic costs, and paucity of valid experimental models. This review article provides an overview of the literature on sex differences in genetic architecture, heritability, epigenetic changes, transcriptomic signatures, and metabolomic profiles in relation to cardiovascular disease traits. We also review the literature on the associations between sex hormones and cardiovascular disease traits and discuss the potential mechanisms underlying these associations, focusing on human studies.