Susceptibility Locus For Myocardial Infarction Research Articles

Fine-Mapping of the PLCL2 Gene Identifies Candidate Variants Associated With Ischaemic Stroke Risk in Metabolic Syndrome Patients.

A genome-wide association study (GWAS) reported PLCL2 on chromosome 3p24. 3 (rs4618210:A>G) as a novel susceptibility locus for myocardial infarction in the Japanese population. As the most common pathological process, atherosclerosis leads to metabolic syndrome (MetS)-related ischaemic stroke (IS) and myocardial infarction. Hypothesizing that polymorphisms of the PLCL2 gene might be associated with the onset and prognosis of IS in MetS patients, we performed the following study in a Chinese Han population. A total of 709 cases (patients with MetS plus IS) and 711 controls (patients with MetS) were enrolled. A fine-mapping strategy was adopted to identify tagged single nucleotide polymorphisms (SNPs) of the PLCL2 gene, and improved multiplex ligation detection reaction (iMLDR) technology was used to genotype the selected SNPs. Logistic regression was used to analyse the values of the selected SNPs for the risk of IS between the cases and controls, adjusting for sex, age, hypertension, dyslipidaemia, hyperglycaemia, smoking and drinking. To compare the mean age of IS onset among different risk score groups, a genetic risk score was constructed for each case. The cumulative risk of IS events in the case group was presented using a cumulative incidence curve. All cases were followed up for 3 months, and functional outcomes were recorded prospectively. Two SNPs (rs4685423 and rs4618210) were significantly related to the risk of IS in MetS patients. For rs4685423, patients who were AA homozygotes were less likely to suffer from IS than C-allele carriers (OR 0.718; 95% CI 0.567–0.909; multivariate-adjusted, P = 0.006). For rs4618210, A-allele carriers were less likely to develop IS than patients who were GG homozygotes (OR 0.679; 95% CI 0.548–0.841; multivariate-adjusted, P < 0.001). As the genetic risk score increased, the mean age at IS onset decreased (log-rank P = 0.010). There was no statistically significant difference in the distribution of the 90-day modified Rankin Scale (mRS) outcomes across the rs4685423 (P = 0.319) or rs4618210 polymorphisms (P = 0.148). Our findings suggested that genetic polymorphisms of PLCL2 might be associated with the onset of MetS-related IS. Further studies are warranted to validate our findings in other ethnic populations.

Genome-wide analysis identifies novel susceptibility loci for myocardial infarction.

While most patients with myocardial infarction (MI) have underlying coronary atherosclerosis, not all patients with coronary artery disease (CAD) develop MI. We sought to address the hypothesis that some of the genetic factors which establish atherosclerosis may be distinct from those that predispose to vulnerable plaques and thrombus formation. We carried out a genome-wide association study for MI in the UK Biobank (n∼472000), followed by a meta-analysis with summary statistics from the CARDIoGRAMplusC4D Consortium (n∼167000). Multiple independent replication analyses and functional approaches were used to prioritize loci and evaluate positional candidate genes. Eight novel regions were identified for MI at the genome wide significance level, of which effect sizes at six loci were more robust for MI than for CAD without the presence of MI. Confirmatory evidence for association of a locus on chromosome 1p21.3 harbouring choline-like transporter 3 (SLC44A3) with MI in the context of CAD, but not with coronary atherosclerosis itself, was obtained in Biobank Japan (n∼165000) and 16 independent angiography-based cohorts (n∼27000). Follow-up analyses did not reveal association of the SLC44A3 locus with CAD risk factors, biomarkers of coagulation, other thrombotic diseases, or plasma levels of a broad array of metabolites, including choline, trimethylamine N-oxide, and betaine. However, aortic expression of SLC44A3 was increased in carriers of the MI risk allele at chromosome 1p21.3, increased in ischaemic (vs. non-diseased) coronary arteries, up-regulated in human aortic endothelial cells treated with interleukin-1β (vs. vehicle), and associated with smooth muscle cell migration in vitro. A large-scale analysis comprising ∼831000 subjects revealed novel genetic determinants of MI and implicated SLC44A3 in the pathophysiology of vulnerable plaques.

Genome-based exome sequencing analysis identifies GYG1, DIS3L and DDRGK1 are associated with myocardial infarction in Koreans.

Myocardial infarction (MI) is a complex disease caused by combination of genetic and environmental factors. Although genome-wide association studies (GWAS) identified more than 46 risk loci which are associated with coronary artery disease and MI, most of the genetic variability inMI still remains undefined. Here, we screened the susceptibility loci for MI using exome sequencing and validated candidate variants in replication sets. We identified that three genes (GYG1, DIS3L and DDRGK1) were associated with MI at the discovery and replication stages. Further research will be required to determine the functional association of these genes with MI risk, and these associations have to be confirmed in other ethnic populations.

4160Identification of STXBP2 as a novel susceptibility locus for myocardial infarction in Japanese individuals by an exome-wide association study

4160Identification of STXBP2 as a novel susceptibility locus for myocardial infarction in Japanese individuals by an exome-wide association study

Identification of STXBP2 as a novel susceptibility locus for myocardial infarction in Japanese individuals by an exome-wide association study.

We performed exome-wide association studies to identify genetic variants—in particular, low-frequency variants with a large effect size—that confer susceptibility to coronary artery disease or myocardial infarction in Japanese. The exome-wide association studies were performed with 12,698 individuals (3488 subjects with coronary artery disease including 2438 with myocardial infarction, 9210 controls) and with the use of the Illumina HumanExome-12 DNA Analysis or Infinium Exome-24 BeadChip. The relation of allele frequencies for 41,339 single nucleotide polymorphisms that passed quality control to coronary artery disease or myocardial infarction was examined with Fisher's exact test. The exome-wide association study for coronary artery disease revealed that 126 single nucleotide polymorphisms were significantly (P <1.21 × 10−6) associated with this condition. Multivariable logistic regression analysis with adjustment for age, sex, and the prevalence of hypertension, diabetes mellitus, and dyslipidemia showed that six of these polymorphisms were related (P < 0.01) to coronary artery disease, but none was significantly (P < 9.92 × 10−5) associated with this condition. The exome-wide association study for myocardial infarction revealed that 114 single nucleotide polymorphisms were significantly (P <1.21 × 10−6) associated with this condition. Multivariable logistic regression analysis with adjustment for covariates revealed that nine of these polymorphisms were related (P < 0.01) to myocardial infarction. Among these nine polymorphisms, rs188212047 [G/T (L212F)] of STXBP2 was significantly (dominant model; P = 4.84 × 10−8; odds ratio, 2.94) associated with myocardial infarction. STXBP2 may thus be a novel susceptibility locus for myocardial infarction in Japanese.

Association of genetic variants with dyslipidemia and chronic kidney disease in a longitudinal population-based genetic epidemiological study.

We previously identified 9 genes and chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke, or chronic kidney disease (CKD) in Japanese individuals by genome-wide or candidate gene association studies. In the present study, we examined the association of 13 polymorphisms at these 10 loci with the prevalence of hypertriglyceridemia, hyper-low-density lipoprotein (LDL) cholesterolemia, hypo-high-density lipoprotein (HDL) cholesterolemia, or CKD in community-dwelling Japanese individuals. The study subjects comprised 6,027 individuals who were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited the Health Care Center at Inabe General Hospital for an annual health checkup, and they were followed up each year (mean follow-up period, 5 years). Longitudinal analysis with a generalized estimating equation and with adjustment for covariates revealed that rs6929846 of butyrophilin, subfamily 2, member A1 gene (BTN2A1) was significantly associated with the prevalence of hypertriglyceridemia (P=0.0001), hyper-LDL cholesterolemia (P=0.0004), and CKD (P=0.0007); rs2569512 of interleukin enhancer binding factor 3 (ILF3) was associated with hyper-LDL cholesterolemia (P=0.0029); and rs2074379 (P=0.0019) and rs2074388 (P=0.0029) of alpha-kinase 1 (ALPK1) were associated with CKD. Longitudinal analysis with a generalized linear mixed-effect model and with adjustment for covariates among all individuals revealed that rs6929846 of BTN2A1 was significantly associated with the serum concentrations of triglycerides (P=0.0011), LDL cholesterol (P=3.3×10−5), and creatinine (P=0.0006), as well as with the estimated glomerular filtration rate (eGFR) (P=0.0004); rs2569512 of ILF3 was shown to be associated with the serum concentration of LDL cholesterol (P=0.0221); and rs2074379 (P=0.0302) and rs2074388 (P=0.0336) of ALPK1 were shown to be associated with the serum concentration of creatinine. Similar analysis among individuals not taking any anti-dyslipidemic medication revealed that rs6929846 of BTN2A1 was significantly associated with the serum concentrations of triglycerides (P=8.3×10−5) and LDL cholesterol (P=0.0004), and that rs2569512 of ILF3 was associated with the serum concentration of LDL cholesterol (P=0.0010). BTN2A1 may thus be a susceptibility gene for hypertriglyceridemia, hyper-LDL cholesterolemia and CKD in Japanese individuals.

Association of genetic variants with coronary artery disease and ischemic stroke in a longitudinal population-based genetic epidemiological study.

Our previous studies identified nine genes and chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke or chronic kidney disease by genome-wide or candidate gene association studies. As coronary artery disease (CAD) and ischemic stroke may share genetic architecture, certain genetic variants may confer susceptibility to the two diseases. The present study examined the association of 13 polymorphisms at these 10 loci with the prevalence of CAD or ischemic stroke in community-dwelling individuals, with the aim of identifying genetic variants that confer susceptibility to the two conditions. Study subjects (170 with CAD, 117 with ischemic stroke and 5,718 controls) were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited for an annual health checkup and they were followed up each year (mean follow-up period, 5 years). Longitudinal analysis with a generalized estimating equation, and with adjustment for age, gender, body mass index, smoking status, the prevalence of hypertension, diabetes mellitus and dyslipidemia and the serum concentration of creatinine, revealed that rs2074380 (G→A) and rs2074381 (A→G) of the α-kinase 1 (ALPK1) gene and rs8089 (T→G) of the thrombospondin 2 (THBS2) gene were significantly (P<2×10-16) associated with the prevalence of CAD, with the AA genotype of rs2074380 and GG genotypes of rs2074381 and rs8089 being protective against this condition. Similar analysis revealed that rs9846911 (A→G) at chromosome 3q28, rs2074381 of ALPK1, rs8089 of THBS2 and rs6046 (G→A) of the coagulation factor VII gene were significantly (P<2×10-16) associated with the prevalence of ischemic stroke, with the GG genotypes of rs9846911, rs2074381 and rs8089 and the AA genotype of rs6046 being protective against this condition. ALPK1 and THBS2 may thus be susceptibility loci for CAD and ischemic stroke.

Association of genetic variants of the α-kinase 1 gene with type 2 diabetes mellitus in a longitudinal population-based genetic epidemiological study.

Previously, our studies identified nine genes and the chromosomal region 3q28 as susceptibility loci for myocardial infarction, ischemic stroke or chronic kidney disease in individuals by genome-wide or candidate gene association studies. The present study examined the possible association of 13 polymorphisms at these 10 loci with the prevalence of type 2 diabetes mellitus (DM) in community-dwelling individuals. Study subjects comprised 6,027 individuals (797 subjects with type 2 DM and 5,230 controls) who were recruited to the Inabe Health and Longevity Study, a longitudinal genetic epidemiological study of atherosclerotic, cardiovascular and metabolic diseases. The subjects were recruited from individuals who visited for an annual health checkup and they were followed up each year (mean follow-up, 5 years). Longitudinal analysis with a generalized estimating equation and with adjustment for age, gender and body mass index (BMI) revealed that rs2116519 (C→T) of FAM78B (P=0.0188), as well as rs2074379 (G→A, P=0.0121) and rs2074388 (A→G, P=0.0053) of ALPK1 were significantly (P<0.05) associated with the prevalence of type 2 DM. Longitudinal analysis with a generalized linear mixed-effect model and with adjustment for age, gender and BMI among all the individuals revealed that rs2116519, rs2074379 and rs2074388 were significantly associated with fasting plasma glucose level (P=0.0352, 0.0017 and 0.0010, respectively) and to blood glycosylated hemoglobin (hemoglobin A1c) content (P=0.0065, 0.0090 and 0.0079, respectively). Similar analysis among individuals not taking antidiabetic medication revealed that rs2074379 and rs2074388 were associated with the fasting plasma glucose level (P=0.0073 and 0.0042, respectively) and blood hemoglobin A1c content (P=0.0142 and 0.0126, respectively), whereas rs2116519 was associated with blood hemoglobin A1c content only (P=0.0470). ALPK1 may thus be a susceptibility gene for type 2 DM.

Association of six genetic variants with myocardial infarction.

Although various genes that confer susceptibility to myocardial infarction (MI) have been identified for Caucasian populations in genome-wide association studies (GWAS), genetic variants related to this condition in Japanese individuals have not been identified definitively. The aim of the present study was to examine an association of MI in Japanese individuals with 29 polymorphisms identified as susceptibility loci for MI or coronary artery disease in Caucasian populations by meta-analyses of GWAS. The study subjects comprised 1,824 subjects with MI and 2,329 controls. Genotypes of the polymorphisms were determined by Luminex bead-based multiplex assay. To compensate for multiple comparisons, we adopted the criterion of a false discovery rate (FDR) of <0.05 for statistical significance for association. Comparisons of allele frequencies by the χ(2) test revealed that rs9369640 of the phosphatase and actin regulator 1 gene (PHACTR1, FDR=0.0007), rs4977574 of the CDKN2B antisense RNA 1 gene (CDKN2B-AS1, FDR=0.0038), rs264 of the lipoprotein lipase gene (LPL, FDR=0.0061), rs599839 of the proline/serine-rich coiled-coil 1 gene (PSRC1, FDR=0.0118), rs9319428 of the fms-related tyrosine kinase 1 gene (FLT1, FDR=0.0118) and rs12413409 of the cyclin and CBS domain divalent metal cation transport mediator 2 gene (CNNM2, FDR=0.0300) were significantly associated with MI. Multivariate logistic regression analysis with adjustment for covariates revealed that rs9369640 (P=0.0005; odds ratio, 0.89), rs4977574 (P=0.0001; odds ratio, 1.50), rs264 (P=0.0405; odds ratio, 0.85), rs599839 (P=0.0003; odds ratio, 0.68), rs9319428 (P=0.0155; odds ratio, 1.20) and rs12413409 (P=0.0076; odds ratio, 0.66) were significantly (P<0.05) associated with MI. PHACTR1, CDKN2B-AS1, LPL, PSRC1, FLT1 and CNNM2 may thus be susceptibility loci for MI in Japanese individuals.

Association of a butyrophilin, subfamily 2, member A1 gene polymorphism with hypertension.

The C→T polymorphism (rs6929846) of the butyrophilin, subfamily 2, member A1 (BTN2A1) gene has been previously identified as a susceptibility locus for myocardial infarction by a genome-wide association study. As hypertension is a major risk factor for myocardial infarction, the association between the BTN2A1 polymorphism, rs6929846, and myocardial infarction may be partly due to its effect on hypertension susceptibility. The aim of the present study was to examine the possible association of rs6929846 with hypertension. The study subjects comprised 5,959 community-dwelling individuals (2,183 subjects with hypertension and 3,776 controls) who were recruited to a population-based cohort study. The rs6929846 genotype was determined by a method that combined polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Comparisons between the genotype distributions (P=0.0090) and allele frequencies (P=0.0051) by the χ2 test revealed that rs6929846 was significantly associated with hypertension. Multivariable logistic regression analysis with adjustment for age, gender, body mass index and smoking status revealed that rs6929846 was significantly associated with hypertension (P=0.0008; odds ratio, 1.29; dominant model), with the minor T allele representing a risk factor for this condition. Among all the individuals, systolic, diastolic and mean blood pressure was significantly higher in the combined group of individuals with the CT or TT genotypes compared to the CC genotype group. BTN2A1 may thus be a susceptibility gene for hypertension. Therefore, determining the genotype for this polymorphism may provide genetic risk assessment information for hypertension.

A genome-wide association study identifies PLCL2 and AP3D1-DOT1L-SF3A2 as new susceptibility loci for myocardial infarction in Japanese.

Despite considerable progress in preventive and therapeutic strategies, myocardial infarction (MI) is one of the leading causes of death throughout the world. A total of 55 susceptibility genes have been identified mostly in European genome-wide association studies (GWAS). Nevertheless, large-scale GWAS from other population could possibly find additional susceptibility loci. To identify as many MI susceptibility loci as possible, we performed a large-scale genomic analysis in Japanese population. To identify MI susceptibility loci in Japanese, we conducted a GWAS using 1666 cases and 3198 controls using the Illumina Human610-Quad BeadChip and HumanHap550v3 Genotyping BeadChip. We performed replication studies using a total of 11,412 cases and 28,397 controls in the Japanese population. Our study identified two novel susceptibility loci for MI: PLCL2 on chromosome 3p24.3 (rs4618210:A>G, P = 2.60 × 10(-9), odds ratio (OR) = 0.91) and AP3D1-DOT1L-SF3A2 on chromosome 19p13.3 (rs3803915:A>C, P = 3.84 × 10(-9), OR = 0.89). Besides, a total of 14 previously reported MI susceptibility loci were replicated in our study. In particular, we validated a strong association on chromosome 12q24 (rs3782886:A>G: P = 1.14 × 10(-14), OR = 1.46). Following pathway analysis using 265 genes related to MI or coronary artery disease, we found that these loci might be involved in the pathogenesis of MI via the promotion of atherosclerosis. In the present large-scale genomic analysis, we identified PLCL2 and AP3D1-DOT1L-SF3A2 as new susceptibility loci for MI in the Japanese population. Our findings will add novel findings for MI susceptibility loci.

Genetic and Clinical Correlates of Early-Outgrowth Colony-Forming Units

Several bone marrow-derived cell populations may have angiogenic activity, including cells termed endothelial progenitor cells. Decreased numbers of circulating angiogenic cell populations have been associated with increased cardiovascular risk. However, few data exist from large, unselected samples, and the genetic determinants of these traits are unclear. We examined the clinical and genetic correlates of early-outgrowth colony-forming units (CFUs) in 1799 participants of the Framingham Heart Study (mean age, 66 years; 54% women). Among individuals without cardiovascular disease (n = 1612), CFU number was inversely related to advanced age (P = 0.004), female sex (P = 0.04), and triglycerides (P = 0.008) and positively related to hormone replacement (P = 0.008) and statin therapy (P = 0.027) in stepwise multivariable analyses. Overall, CFU number was inversely related to the Framingham risk score (P = 0.01) but not with prevalent cardiovascular disease. In genome-wide association analyses in the entire sample, polymorphisms were associated with CFUs at the MOSC1 locus (P = 3.3 × 10(-7)) and at the SLC22A3-LPAL2-LPA locus (P = 4.9 × 10(-7)), a previously replicated susceptibility locus for myocardial infarction. Furthermore, alleles at the SLC22A3-LPAL2-LPA locus that were associated with decreased CFUs were also related to increased risk of myocardial infarction (P = 1.1 × 10(-4)). In a community-based sample, early-outgrowth CFUs are inversely associated with select cardiovascular risk factors. Furthermore, genetic variants at the SLC22A3-LPAL2-LPA locus are associated with both decreased CFUs and an increased risk of myocardial infarction. These findings are consistent with the hypothesis that decreased circulating angiogenic cell populations promote susceptibility to myocardial infarction.

Association of a polymorphism of BTN2A1 with dyslipidemia in East Asian populations

We previously identified rs6929846 of the butyrophilin, subfamily 2, member A1 gene (BTN2A1) as a susceptibility locus for myocardial infarction in Japanese individuals by a genome-wide association study. The aim of the present study was to examine the relation of the rs6929846 polymorphism of BTN2A1 to dyslipidemia in Japanese and Korean populations, given that dyslipidemia is an important risk factor for myocardial infarction. A total of 10,953 individuals from three independent subject panels were examined. The relations of the rs6929846 polymorphism of BTN2A1 to serum concentrations of triglycerides, high-density lipoprotein (HDL)-cholesterol and low-density lipoprotein (LDL)-cholesterol were examined in each subject panel. The C→T polymorphism (rs6929846) of BTN2A1 was significantly associated with serum concentrations of triglycerides in Japanese subject panels A (P=0.0004) and B (P=0.0010), and in the Korean population (P=0.0095), with the minor T allele being related to an increased serum concentration of triglycerides. The rs6929846 was associated with serum concentrations of HDL-cholesterol in Japanese subject panels A (P=0.0047) and B (P=0.0015), with the T allele being related to a decreased serum concentration of HDL-cholesterol, but not in the Korean population. This polymorphism was associated with the serum concentration of LDL-cholesterol only in Japanese subject panel B (P=0.0059), with the T allele being related to an increased serum concentration of LDL-cholesterol. The results suggest that BTN2A1 may be a susceptibility gene for hypertriglyceridemia in East Asian populations and for low serum HDL-cholesterol in the Japanese population.

Genetic risk for myocardial infarction in Japanese individuals with or without chronic kidney disease

Although chronic kidney disease (CKD) is recognized as an important risk factor for myocardial infarction (MI), genetic factors underlying predisposition to MI in individuals with or without CKD remain largely unknown. The aim of the present study was to identify genetic variants that confer susceptibility to MI in individuals with or without CKD in order to allow prediction of genetic risk for such individuals separately. The study population comprised a total of 4344 individuals, including 1247 individuals with CKD (506 subjects with MI and 741 controls) and 3097 individuals without CKD (833 subjects with MI and 2264 controls). The 150 polymorphisms examined in this study were selected by genome-wide association studies of ischemic stroke and MI with the use of the GeneChip Human Mapping 500K Array Set (Affymetrix) and determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. In individuals with CKD, no polymorphism was significantly related to MI. In individuals without CKD, an initial screen by the Chi-square test revealed that the Cyright curved arrow T polymorphism of CLEC16A (rs9925481) and the Aright curved arrow G polymorphism of LAMA3 (rs12373237) were significantly (false discovery rate for allele frequencies of <0.05) associated with MI. Subsequent multivariable logistic regression analysis with adjustment for covariates revealed that the Cright curved arrow T polymorphism of CLEC16A (dominant model; P=0.0003; odds ratio, 0.66) and the Aright curved arrow G polymorphism of LAMA3 (recessive model; P=0.0087; odds ratio, 0.75) were significantly (P<0.05) associated with MI. A stepwise forward selection procedure also revealed that these polymorphisms were significant and independent determinants of MI. CLEC16A and LAMA3 may be susceptibility loci for MI in Japanese individuals without CKD. Determination of genotypes for CLEC16A and LAMA3 may prove informative for assessment of the genetic risk for MI in such individuals.

Interactions and associations of paraoxonase gene cluster polymorphisms with myocardial infarction in a Pakistani population

Polymorphisms of paraoxonase gene (PON) cluster have been investigated in numerous studies for their association with myocardial infarction (MI) but the results have been conflicting. Epistasis and gene-environment interactions at this locus could possibly modulate susceptibility toward MI and account for the discrepancies. We carried out a case-control study (211 MI patients and 370 control subjects) to test association of PON cluster polymorphisms with MI, their interactions with each other and with smoking. Genotyping was performed by PCR-restriction fragment length polymorphism based assays. The Q192R, C-108T, and A148G polymorphisms were associated with MI. Two haplotypes consisting of C-108T, C311S, and A148G, having allele frequencies of 0.17 and 0.14 in the control population, predisposed to MI (global haplotype statistic chi2 = 34.74, df = 15, p = 0.0027). Multifactor dimensionality reduction analysis showed a significant three-locus model (p = 0.02) involving these three polymorphisms, suggesting a potential gene-gene interaction between PON1 and PON2. These polymorphisms also interacted with smoking, in a three-locus and a four-locus model (p = 0.01 and p = 0.05, respectively). Additionally, the R192 allele may advance the age-at-onset of MI. The PON cluster appears to be a susceptibility locus for MI in Pakistani population, and the susceptibility is modulated through gene-gene and gene-environment interactions.

Association of Transforming Growth Factor-β1 Gene Polymorphisms With Myocardial Infarction in Patients With Angiographically Proven Coronary Heart Disease

Transforming growth factor (TGF)-beta1 (TGF-beta1) is a multifunctional cytokine that exhibits vasculoprotective properties. Production and plasma levels of TGF-beta1 are influenced by polymorphisms in the TGF-beta1 gene (TGFB1). We investigated whether the -509C/T (rs1800469), 868T/C (rs1982073), 913G/C (rs1800471), and 11929C/T (rs1800472) polymorphisms of TGFB1 are associated with myocardial infarction. The study population consisted of 3657 patients with myocardial infarction (885 women and 2772 men) and 1211 control individuals (598 women and 613 men) with angiographically normal coronary arteries and without signs or symptoms of myocardial infarction. Polymorphism-related genotypes were determined with TaqMan assays and haplotypes were estimated from the genotype data. The -509C/T polymorphism and -509C/868T/913G/11929C (CTGC) haplotype were associated with myocardial infarction in men, independently from the potentially confounding factors age, arterial hypertension, hypercholesterolemia, cigarette smoking, and diabetes mellitus. Lower risks of myocardial infarction were observed among the carriers of the -509CC genotype (adjusted odds ratio [OR], 0.49; 95% confidence interval [CI], 0.27 to 0.87; P=0.014) and homozygous carriers of the CTGC haplotype (adjusted OR, 0.61; 95% CI, 0.38 to 0.98; P=0.042) than among the noncarriers of this genotype or haplotype. None of the genotypes (P> or =0.37) or haplotypes (P> or =0.35) was associated with myocardial infarction in women. Positive association findings in this study suggest that TGFB1 is a susceptibility locus for myocardial infarction.

Lack of association of polymorphisms of the lymphotoxin alpha gene with myocardial infarction in Japanese.

Vascular inflammation plays an important role in the development of myocardial infarction (MI). Lymphotoxin alpha (LTA) is a cytokine with multiple functions in regulation of the immune system and inflammatory reactions. The aim of this study was to examine whether polymorphisms of the LTA gene are associated with the risk of MI in Japanese men and women. A case-control association study was performed for the 252A-->G and 804C-->A polymorphisms of the LTA gene and the prevalence of MI. The study population comprised 3,689 unrelated Japanese individuals (2,486 men, 1,203 women), including 1891 patients with MI (1,493 men, 398 women) and 1798 control subjects (993 men, 805 women). Among the control subjects 257 individuals (108 men, 149 women) who had none of the conventional risk factors for coronary artery disease (CAD) were defined as low-risk controls. Genotypes for the two polymorphisms were determined with a fluorescence-based allele-specific DNA primer assay system. Among all study subjects the 252A-->G and 804C-->A polymorphisms exhibited linkage disequilibrium. No association of either polymorphism with MI was detected in men or in women in comparisons with total control or low-risk control subjects. However, each of the two polymorphisms was associated with the prevalence of type 2 diabetes mellitus both in men with MI and in those without MI in a recessive genetic model. No association was detected between the polymorphisms and other conventional risk factors for CAD. The LTA gene thus does not appear to be a susceptibility locus for MI in Japanese men or women, although it might affect susceptibility to type 2 diabetes in Japanese men.

A comprehensive linkage analysis for myocardial infarction and its related risk factors

Coronary artery disease and myocardial infarction (MI) are leading causes of death in the western world. Numerous studies have shown that risk factors such as diabetes mellitus, arterial hypertension and hypercholesterolemia contribute to the development of the disease. Although each risk factor by itself is partly under genetic control, a positive family history is an independent predictor, which suggests that there are additional susceptibility genes. We have scanned the whole genome in 513 families to identify chromosomal regions linked to myocardial infarction and related risk factors that are known to be under genetic control. Here we show, by using variance component analysis and incorporating risk factors, that risk of myocardial infarction maps to a single region on chromosome 14 with a significant lod score of 3.9 (pointwise P=0.00015, genome-wide P<0.05), providing evidence of a principal MI locus. To characterize this locus we analyzed each risk factor by itself. Serum concentrations of lipoprotein (a) show linkage to both the apolipoprotein (a) locus (lod score 26.99) and a new locus on chromosome 1 (lod score 3.8). There is suggestive linkage for diabetes mellitus on chromosome 6 (lod score 2.96), for hypertension on chromosomes 1 and 6, for high-density and low-density lipoprotein cholesterol on chromosomes 1 and 17, and for triglyceride concentrations on chromosome 9. Although some of these risk factors overlap with previously identified loci, none overlaps with the newly identified susceptibility locus for myocardial infarction and coronary artery disease.