Haplotype Analysis of PPARγ Gene Polymorphisms and the Lipoprotein (a) Level.

BACKGROUND: Lipoprotein (a) [Lp(a)], as an independent risk factor for cardiovascular disease, is more likely to be genetically determined according to the increasing evidence of epidemiologic and clinical studies in recent years. Peroxisome proliferator-activated receptor (PPAR) γ, the ligand-activated transcription factors, was considered as an indispensable role in the process of lipid metabolism. This study was designed to explore the associations of three single-nucleotide polymorphisms (SNPs) and the haplotypes of the peroxisome proliferator-activated receptor (PPAR)γ gene with the level of Lp(a). METHODS: Participants were recruited under the framework of the PMMJS (The Prevention of Metabolic Syndrome (MS) and Multi-metabolic Disorders in Jiangsu Province of China Study) from Apr 1999 to Jun 2004. Overall, 644 subjects were randomly selected and 3 SNPs of PPARγ gene (rs10865710, rs1805192, rs4684847) were genotyped. RESULTS: After adjusting for age, sex, cigarette smoking, alcohol drinking, waist circumference and body mass index, rs4684847 was significantly associated with Lp (a). The presence of the rs4684847 T allele (CT+TT) have a lower level of Lp (a) than the allele (CC) in the dominant model, mean difference was -27.30 (95% CI: -52.88∼-1.73) mg/L, P<0.05. G-P-T and G-A-T haplotype were associated with lower levels of Lp (a) (P=0.0041 and <0.0001), mean difference was 49.79 (95% CI: -97.52∼-2.06) mg/L and 17.75 (95% CI: -25.75∼-9.75) mg/L. CONCLUSION: PPAR gamma polymorphisms (rs10865710, rs1805192, rs4684847) and haplotypes may be the genetic risk factors for Lp (a) level.

Analysis on the association between PPARα/γ polymorphisms and lipoprotein(a) in a Chinese Han population.

Lipoprotein(a) [Lp(a)], a low-density lipoprotein-like particle, is recognized as an independent risk factor for atherosclerosis, cardiovascular diseases, and diabetic vascular diseases. Our recent studies revealed that the single nucleotide polymorphisms (SNPs) of peroxisome proliferator-activated receptors (PPARα/δ/γ) gene are involved in the regulation of lipid storage and metabolism. In order to investigate the relationships between the SNPs of PPARα/γ gene and plasma levels of Lp(a), 644 participants were randomly selected from Chinese Han population in the present study. As the results shown, Lp(a) was significantly associated with L162V (rs1800206) in PPARα. Compared with those subjects with widetype (LL), significantly higher Lp(a) concentration was determined in the individuals with mutant (LV + VV) (mean difference: 49.07 mg/l, 95% CI 23.32-74.82 mg/l, p = 0.0002). Moreover, with generalized multifactor dimensionality reduction analysis, our present results indicated that there was a significant association between plasma Lp(a) level and gene-gene interaction among the polymorphisms rs1800206, rs135539 in PPARα and rs10865710, rs1805192, and rs4684847 in PPARγ. Therefore, our presented study indicated that PPARα/γ polymorphisms should be involved in the regulation of plasma Lp(a) in independently and/or in an interactive manner, suggesting that PPARα/γ gene may influence the risk of hypertension, cardiovascular diseases, and dyslipidemia by regulating Lp(a) level.

[Association of both peroxisome proliferator-activated receptor, gene-gene interactions and the lipid accumulation product].

OBJECTIVE: To investigate the association of ten single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptors (PPARα, δ, γ) with lipid accumulation product (LAP) and the additional role of a gene-gene interactions among the 10 SNPs. METHODS: Participants were recruited under the framework of the PMMJS (Prevention of Multiple Metabolic Disorders and Metabolic Syndrome in Jiangsu province) cohort populations survey in the urban community of Jiangsu province of China. A total of 820 subjects were randomly selected and no individual was related. Ten SNPs (rs135539, rs4253778, rs1800206, rs2016520, rs9794, rs10865710, rs1805192, rs709158, rs3856806 and rs4684847) were selected from the HapMap database, which covered PPARα, PPARδ and PPARγ. A linear regression model was used to analyze the relations between ten SNPs in the PPARs and LAP. Mean difference (Difference) and 95% confident interval (95%CI)were calculated. Interactions were explored by using the method of Generalized Multifactor Dimensionality Reduction (GMDR). RESULTS: After adjusting the factors as age, gender, smoking status, occupational physical activity, educational level, high-fat diet as well as low-fiber diet, both rs1800206, s1805192 and rs3856806 were significantly associated with the increased level of LAP. Difference (95% CI) values were 32.47 (22.62-42.31), 12.97 (4.61-21.33) and 12.49 (4.24-20.75). Whereas rs2016520 was significantly associated with the decreased level of LAP. Difference (95%CI) values was -14.67 ( -22.97--6.55). GMDR analysis showed a significant gene-gene interaction among rs135539, rs1800206 of PPARα, rs2016520 of PPARδ and rs10865710, rs3856806, rs709158, rs1805192, rs4684847 of PPARγ for eight-dimension models (P < 0.05), in which prediction accuracy was 0.5902 and cross-validation consistency was 10/10. CONCLUSION: The rs1800206 of PPARα and rs1805192, rs3856806 of PPARγ were significantly associated with the increased level of LAP; rs2016520 of PPARδ was associated with the decreased level of LAP. There was a gene-gene interaction between multiple SNPs.