Interleukin-6 gene polymorphism is an age-dependent risk factor for myocardial infarction in men

The Role of Plasma Interleukin-6 Levels on Atherosclerotic Cardiovascular Disease and Cardiovascular Mortality Risk Scores in Javanese Patients with Chronic Kidney Disease

Interleukin-6 (IL-6) has been identified as an important pro-inflammatory factor involved in mediating the severity of chronic kidney disease (CKD). This study sought to determine the effect of plasma IL-6 levels on atherosclerotic cardiovascular disease (ASCVD) and cardiovascular mortality risk scores in Javanese CKD patients. We also analyzed the frequency of IL-6 G174C single nucleotide polymorphism (SNP) in the population. This study was a cross-sectional study involving seventy-three patients of Javanese ethnic origin with stable chronic kidney disease. We assessed the ASCVD risk score, cardiovascular mortality score, genotyping of IL-6 G174C SNP, and plasma IL-6 levels in these patients. The genotype distribution and allele frequencies of the IL-6 G174C SNP were predominated by the G genotype/allele (GG: 97.26%, GC: 1.37%, CC: 1.37%, G-allele: 97.95%, and C-allele: 2.05%). Despite the fact that plasma IL-6 levels did not directly affect cardiovascular mortality risk, further analysis revealed its direct effect on the ASCVD risk score (path coefficient = 0.184, p = 0.043, 95% CI = 0.018−0.380), which in turn affected cardiovascular mortality risk (path coefficient = 0.851, p = <0.01, 95% CI = 0.714−0.925). In conclusion, plasma IL-6 levels play important roles on ASCVD risk and cardiovascular mortality risk in Javanese patients with CKD.

Association of interleukin 6 -174 G/C polymorphism with coronary artery disease and circulating IL-6 levels: a systematic review and meta-analysis

INTRODUCTION

Circulating IL-6 levels and at least one polymorphic form of IL6 gene (IL6 -174 G/C, rs1800795) have been shown to be independently associated with coronary artery disease (CAD) by several investigators. Despite more than 12 published meta-analyses on this subject, association of -174 G/C with CAD, especially amongst distinct ancestral population groups remain unclear. We, therefore, conducted a systematic review and an updated meta-analysis to comprehensively ascertain the association of IL6 -174 G/C with CAD and circulating IL-6 levels.

MATERIALS AND METHODS

Relevant case-control/cohort studies investigating association of -174 G/C with CAD and circulating IL-6 levels were identified following a comprehensive online search. Association status for CAD was determined for the pooled sample, as well as separately for major ancestral subgroups. Association status for circulating IL-6 levels was assessed for the pooled sample, as well as separately for CAD cases and CAD free controls. Study-level odds ratios (OR) and 95% confidence intervals (CI) were pooled using random/fixed-effects model.

RESULTS

Quantitative synthesis for the CAD endpoint was performed using 55 separate qualifying studies with a collective sample size of 51,213 (19,160 cases/32,053 controls). Pooled association of -174 G/C with CAD was found to be statistically significant through dominant (OR 1.15; 95% CI 1.05-1.25, p = 0.002) as well as allelic genetic model comparisons (OR 1.13, 95% CI 1.06-1.21, p = 0.0003). This effect was largely driven by Asian and Asian Indian ancestral subgroups, which also showed significant association with CAD in both genetic model comparisons (OR range 1.29-1.53, p value range ≤ 0.02). Other ancestral subgroups failed to show any meaningful association. Circulating IL-6 levels were found to be significantly higher amongst the 'C' allele carriers in the pooled sample (Standard mean difference, SMD 0.11, 95% CI 0.01-0.22 pg/ml, p = 0.009) as well as in the CAD free control subgroup (SMD 0.10, 95% CI 0.02-0.17 pg/ml, p = 0.009), though not in the CAD case subgroup (SMD 0.17, 95% CI = - 0.02 to 0.37, p = 0.12).

CONCLUSIONS

The present systematic review and meta-analysis demonstrate an overall association between IL6 -174 G/C polymorphism and CAD, which seems to be mainly driven by Asian and Asian Indian ancestral subgroups. Upregulation of plasma IL-6 levels in the 'C' allele carriers seems to be at least partly responsible for this observed association. This warrants further investigations with large, structured case-control studies especially amongst Asian and Asian Indian ancestral groups.

Polymorphisms of Pro-Inflammatory IL-6 and IL-1β Cytokines in Ascending Aortic Aneurysms as Genetic Modifiers and Predictive and Prognostic Biomarkers

Background: Previous studies have demonstrated that polymorphisms involved in immune genes can affect the risk, pathogenesis, and outcome of thoracic ascending aortic aneurysms (TAAA). Here, we explored the potential associations of five functional promoter polymorphisms in interleukin-6 (IL-6), IL-1B, IL-1A, IL-18, and Tumor necrosis factor (TNF)A genes with TAAA. Methods: 144 TAAA patients and 150 age/gender matched controls were typed using KASPar assays. Effects on telomere length and levels of TAAA related histopathological and serological markers were analyzed. Results: Significant associations with TAAA risk were obtained for IL-6 rs1800795G>C and IL-1B rs16944C>T SNPs. In addition, the combined rs1800795C/rs16944T genotype showed a synergic effect on TAAA pathogenesis and outcome. The combined rs1800795C/rs16944T genotype was significantly associated with: (a) higher serum levels of both cytokines and MMP-9 and -2; (b) a significant CD3+CD4+CD8+ CD68+CD20+ cell infiltration in aorta aneurysm tissues; (c) a significant shorter telomere length and alterations in telomerase activity. Finally, it significantly correlated with TAAA aorta tissue alterations, including elastic fragmentation, medial cell apoptosis, cystic medial changes, and MMP-9 levels. Conclusions: the combined rs1800795C/rs16944T genotype appears to modulate TAAA risk, pathogenesis, and outcome, and consequently can represent a potential predictive and prognostic TAAA biomarker for individual management, implementation of innovative treatments, and selection of the more proper surgical timing and approaches.

Systematic review and meta-analysis of association of polymorphisms in inflammatory cytokine genes with coronary artery disease

BACKGROUND

It has comprehensively been acknowledged that a genetic contribution, especially in immune inflammatory players, such as interleukin (IL)-6 and tumor necrosis factor (TNF)-α, are critically involved in the pathophysiology of coronary artery disease (CAD). This meta-analysis study aimed to reach a conclusive understanding of the role of genetic polymorphisms, including IL6 gene C572G (rs1800796) and G174C (rs1800795) as well as TNFA gene G238A (rs361525) and G308A (rs1800629) in susceptibility to CAD.

METHODS

Two major databases, namely MEDLINE and Scopus, were searched to find the studies surveying the mentioned polymorphisms and CAD susceptibility up to July 2020. Association comparison between the polymorphisms and CAD susceptibility were assessed using pooled odds ratio (OR) and their corresponding 95% confidence interval (CI).

RESULTS

This meta-analysis study was conducted on 69 papers (73 population studies), comprising 5062 patients and 8446 controls for IL6 gene rs1800796 (17 studies), 13801 patients and 16215 controls for IL6 gene rs1800795 (38 studies), 1439 patients and 2850 controls for TNFA gene rs361525 (5 studies), and 5051 patients and 3958 controls for TNFA gene rs1800629 (13 studies), according to inclusion and exclusion criteria. There were statistically positive association between all genetic comparisons of IL6 gene rs1800795 polymorphism and the CAD risk. Moreover, the recessive model (CC vs. CG + GG) in IL6 gene rs1800796 polymorphism had marginally significant association with decreased risk of CAD. None of the TNFA gene polymorphisms were associated with CAD risk.

CONCLUSIONS

The meta-analysis revealed the positive association of IL6 gene rs1800795 polymorphism in susceptibility to CAD.

Investigating the Contribution of NPSR1, IL-6 and BDNF Polymorphisms to Depressive and Anxiety Symptoms in Hemodialysis Patients

AIMS

Psychological symptoms are prevalent in hemodialysis (HD) patients. Previous investigations showed that brain-derived neurotrophic factor (BDNF) and interleukin-6 (IL-6) as well as the interaction with neuropeptide S receptor 1 (NPSR1) are linked to the development of psychological distress. This study examined the association of polymorphisms of genes encoding these proteins with depression and anxiety in a representative group of Jordanian HD patients.

METHODS

A total of 302 HD patients were involved in the study and categorized into three groups based on the Hospital Anxiety and Depression Scale, HADS-D or HADS-A scores as follows: normal (<7), mild (8-10) and moderate-severe (11-21). Single nucleotide polymorphism (SNP) of NPSR1 Asn107Ile (rs324981), IL-6 G174C (rs1800795), and BDNF Val66Met (rs6265) was genotyped using blood samples.

RESULTS

The frequency of Ile-allele of NPSR1 Asn107Ile was significantly higher in patients with moderate-severe HADS-A scores versus normal (53% vs. 40.8%, p = .035). Using ordinal regression analysis, Asn-allele of NPSR1 polymorphism was nominally significantly associated with a lower risk of anxiety (OR = 0.57, CI: 0.33-0.97, p = .038) after adjusting for other covariates. A marginally significant difference in genotype distribution of IL-6 G174C was observed among patients according to HADS-D scores (p = .05). Furthermore, carriers of IL-6174 CC genotype showed lower median IL-6 serum concentration versus carriers of GG genotype (5.2 vs. 1.35 pg/mL, p < .05).

CONCLUSIONS

The results support the genetic role of NPSR1 in the pathogenesis of anxiety and suggest that carriers of NPSR1 Ile-allele are at increased risk of anxiety in HD patients. Neither BDNF Val66Met nor IL-6 G174C were linked to psychological symptoms. Future studies among other ethnicities are necessary to verify the observations.

Interleukin 6 (rs1800795) gene polymorphism is associated with cardiovascular diseases: a meta-analysis of 74 studies with 86,229 subjects

Cardiovascular diseases (CVD) are group of complex and multifactorial pathologies, in which interleukin-6 (IL-6) gene polymorphisms have been associated with several components of the CVD. Thus, in this study, we thoroughly reviewed and meta-analyzed evidence on the association between the IL-6 (rs1800795) gene polymorphism and CVD. We systematically searched in the PubMed, Web of Sciences, and Scopus databases. The analyses were performed using five study groups based on (1) a combined pool of the overall populations, (2) the country of birth, (3) the continent of birth, (4) the diagnosis and (5) both location (country or continent) and diagnosis. The analysis included the allelic, homozygote, heterozygote, dominant and recessive models. The meta-analysis showed that -174G>C (rs1800795) is a risk factor for CVD (allelic: OR=1.06, CI 95%=1.02-1.10. Z p value <0.0001; homozygous: OR=1.11, CI 95%=1.03-1.19, Z p value= 0.002; heterozygous: OR=1.08, CI 95%=1.03-1.21, Z p value= 0.003; dominant: OR= 1.12, CI 95%= 1.07-1.18, Z p value= 0.001) and that this risk increases in the Chinese population. Additionally, we found that carriers of the C allele of 174G>C (rs1800795) polymorphism have an increase in the risk of coronary artery disease under the hereditary models assessed in the study. Using robust data, we found that IL-6 (rs1800795) -174G>C gene polymorphism is associated with CVD risk.

An Evidence-Based Meta-Analysis on the Roles of Functional Interleukin-6 Polymorphisms in Coronary Artery Disease

Recently, the relationship between functional interleukin-6 (IL-6) polymorphisms and coronary artery disease (CAD) was extensively studied, with controversial findings. Therefore, we conducted this meta-analysis to better elucidate the relationship between these polymorphisms and the risk of CAD. A total of 57 case-control studies were finally included. The overall analyses showed that IL-6 -174G>C and -572G>C polymorphisms were significantly associated with the risk of CAD, the C allele of -174G>C (G versus C, odds ratio [OR] = 0.82, confidence interval [95% CI] = 0.75-0.89) and -572G>C polymorphisms (G versus C, OR = 0.82, 95% CI = 0.74-0.92) conferred an increased susceptibility to CAD. Further subgroup analyses yielded similar positive results for -174G>C polymorphism in Asian and Caucasian populations, and for -572G>C polymorphism in Asian and African populations. In conclusion, our findings suggest that IL-6 -174G>C and -572G>C polymorphisms may serve as potential genetic markers of CAD.

Relative lymphocyte count as an indicator of 3-year mortality in elderly people with severe COPD

BACKGROUND

Prognostic stratification of elderly patients with chronic obstructive pulmonary disease (COPD) is difficult due to the wide inter-individual variability in the course of the disease. No marker can exactly stratify the evolution and natural history of COPD patients. Studies have shown that leukocyte count is associated with increased risk of mortality in COPD patients. The aim of this study was to evaluate the possible role of relative lymphocyte count as a risk marker for mortality in elderly patients with COPD.

METHODS AND RESULTS

This is a3-year prospective study. A total of 218patients, mean age 75.2±7 years, with moderate to severe COPD and free from conditions affecting lymphocyte count were enrolled. The population was divided into two groups according to the relative lymphocyte count, with a cut-off of 20%. Eighty-five patients (39%) had a relative lymphocyte count ≤20%. Three-year mortality rates from any cause in patients with relative lymphocyte count ≤ or > 20% were 68 and 51%, respectively (p = 0.0012). Survival curve analysis showed higher mortality in patients with relative lymphocyte count ≤20% (p = 0.0005). After adjustment for age and sex, the hazard ratio for mortality risk according to lymphocyte count was 1.79 (95% confidence interval [CI]: 1.26-2.57, p = 0.0013), even in the analysis limited to the 171 patients without congestive heart failure (1.63; 95% CI: 1.03-2.58, p = 0.038).

CONCLUSIONS

Low relative lymphocyte count was associated with higher mortality in elderly patients with severe COPD.

Dual Effect of IL-6 -174 G/C Polymorphism and Promoter Methylation in the Risk of Coronary Artery Disease Among South Indians

Inflammation plays an important role in the pathogenesis of atherosclerosis and coronary syndromes; moreover, various lines of evidence suggest that genetic factors do contribute to the risk of coronary artery disease (CAD). The proinflammatory cytokine IL-6 is a central mediator of inflammation associated with CAD. The present study is aimed to investigate the association of single nucleotide polymorphism in the promoter region of the IL-6 gene (-174 G > C) and methylation with the susceptibility of CAD. Genotyping of IL-6 -174 G/C polymorphism was performed by PCR-RFLP. Methylation-specific PCR method was used to study the IL-6 gene promoter methylation. Analysis of 470 subjects (265 CAD patients and 205 controls) showed association of the -174 G/C variant with the CAD risk in dominant model (OR 1.58, 95% CI, 1.024-2.23, P = 0.04). Further, the analysis of the distribution of genotypes and alleles of -174 G > C polymorphism according to clinical features of CAD, revealed significant association of genotype and allele (OR 1.86, 95% CI 1.18-2.84 P = 0.01, and OR 1.71, 95% CI 1.09-2.23 P = 0.02 respectively) with diabetes, and we found no association with hypertension (OR 0.95, 95% CI 0.57-1.59, P = 0.8). We also analyzed the methylation status of IL-6 promoter region between cases and controls showed significant hypo methylation in CAD subjects (OR 2.36, 95% CI 1.51-4.259, P = 0.006). Additionally, GC, CC genotypes and C allele carriers show hypomethylation in CAD cases compared to controls (54.58 vs. 76.85%, 29.83 vs. 40% respectively). In conclusion, the promoter polymorphism -174 G/C is associated with CAD risk and further carriers of 'C' allele at -174 locus showed significant hypo methylation which could contribute to increased risk of CAD. The present study highlights the association of allele and genotypes with differential DNA methylation of CpG islands in the IL-6 promoter region which may affect IL-6 gene regulation.

IL6-174 G>C Polymorphism (rs1800795) Association with Late Effects of Low Dose Radiation Exposure in the Portuguese Tinea Capitis Cohort

Head and neck cancers, and cardiovascular disease have been described as late effects of low dose radiation (LDR) exposure, namely in tinea capitis cohorts. In addition to radiation dose, gender and younger age at exposure, the genetic background might be involved in the susceptibility to LDR late effects. The -174 G>C (rs1800795) SNP in IL6 has been associated with cancer and cardiovascular disease, nevertheless this association is still controversial. We assessed the association of the IL6-174 G>C SNP with LDR effects such as thyroid carcinoma, basal cell carcinoma and carotid atherosclerosis in the Portuguese tinea capitis cohort. The IL6-174 G>C SNP was genotyped in 1269 individuals formerly irradiated for tinea capitis. This sampling group included thyroid cancer (n = 36), basal cell carcinoma (n = 113) and cases without thyroid or basal cell carcinoma (1120). A subgroup was assessed for atherosclerosis by ultrasonography (n = 379) and included matched controls (n = 222). Genotypes were discriminated by real-time PCR using a TaqMan SNP genotyping assay. In the irradiated group, we observed that the CC genotype was significantly associated with carotid plaque risk, both in the genotypic (OR = 3.57, CI = 1.60–7.95, p-value = 0.002) and in the recessive (OR = 3.02, CI = 1.42–6.42, p-value = 0.004) models. Irradiation alone was not a risk factor for carotid atherosclerosis. We did not find a significant association of the IL6-174 C allele with thyroid carcinoma or basal cell carcinoma risk. The IL6-174 CC genotype confers a three-fold risk for carotid atherosclerotic disease suggesting it may represent a genetic susceptibility factor in the LDR context.

Association between the interleukin-6 genetic polymorphism 174 G/C and thrombosis disorder risk: Meta-analysis of 10,549 cases and 19,316 controls

Studies investigating the association between interleukin-6 (IL-6) gene-174 G/C polymorphism (rs1800795) and thrombosis disorder risk reported conflicting results. The aim of our study was to assess the association between the IL-6 gene 174 G/C polymorphisms and the risk of thrombosis disorders.Thirty four case-control studies in 29 articles with 29,865 individuals were incorporated in this meta-analysis by searching the public databases including Medline, Embase, and ISI Web of Science databases as of June 1st, 2015. The odds ratio (OR) and 95% confidence interval (95%CI) were used to assess the strength of the association.By pooling all studies, there was marginal association between and the risk of thrombotic disorders (1.09[0.97-1.22]), arterial thrombotic disorders (1.08[0.95-1.23]), and myocardial infarction (MI, 1.14[0.99-1.32]) under dominant genetic effect (C carriers vs GG). In subgroup analyses stratified by ethnicity, study scale, thrombotic category, and country, the results indicated that IL-6 gene-174 G/C polymorphism was significantly associated with increased risk of thrombotic disorders given the conditional such as Asians, large sample-sized, MI, population-based, and Indian studies (C carriers vs GG: 1.39 [1.13-1.72] and C allele vs G allele: 1.36 [1.18-1.56] for Asian; C carriers vs GG: 1.15 [1.01-1.31] and C allele vs G allele: 1.12 [1.01-1.23] for large sample-sized studies; C allele vs G allele: 1.10 [1.03-1.18] for population-based studies; and C carriers vs GG: 1.40 [1.19-1.65] for Indian studies). We did not observe significant association between IL-6-174 G/C and the risk of Caucasians, small sample-sized studies, stroke and venous studies, and other country studies.This meta-analysis suggests that IL-6 gene-174 G/C polymorphism may be marginally associated with risk of thrombotic disorders, arterial disorders, MI especially for Asian, Indian, population-based, and large sample-sized studies. More studies with larger sample size and well-designed studies might be warranted.

Effect of G(-174)C polymorphism in interleukin-6 gene on cardiovascular disease in type 2 diabetes patients

Interleukin-6 (IL-6) is an important pro-inflammatory cytokine of relevance to cardiovascular diseases. The aim of this case-control study was to evaluate the association between the G(-174)C functional polymorphism in the IL-6 gene and risk of cardiovascular disease (CVD) in type 2 diabetes patients. We examined 1090 patients with T2DM and 612 controls. All subjects were genotyped for the G(-174)C polymorphism by polymerase chain reaction (PCR) and restriction analysis. There were no significant differences in the distribution of genotypes and alleles between T2DM patients and healthy controls. Significantly higher C allele frequency was observed in CVD+ patients compared to CVD- subgroup (53% vs. 32%, p<0.0001). The odds ratio for C allele was 2.4 (95% CI 1.99-2.9, p<0.0001) and for CC genotype 4.55 (95% CI 3.12-6.63, p<0.000). When the distribution of G(-174)C polymorphism was compared in subgroups with different clinical phenotypes of CVD, a significant association of CC genotype with myocardial infarction was observed. Forty eight percent of patients with MI had the CC genotype compared to 22% of patients without MI (p<0.0001). In conclusion, type 2 diabetes patients carrying the C allele of the IL-6 G(-174)C polymorphism have a significantly increased risk of CVD.

Common polymorphisms in the interleukin-6 gene and myocardial infarction risk: a meta-analysis

BACKGROUND

Interleukin-6 (IL-6) plays a critical role in the development and progression of cardiovascular disease. Emerging evidence suggests that two common polymorphisms (-174 G/C and -572 G/C) in the IL-6 gene might have an impact on an individual's susceptibility to myocardial infarction (MI), but individually published results are inconclusive. This meta-analysis aimed to derive a more precise estimation of the relationship between IL-6 -174 G/C and -572 G/C polymorphisms and MI risk.

METHOD

An extensive literary search for relevant studies was conducted in PubMed, Embase, Web of Science, Cochrane Library, CISCOM, CINAHL, Google Scholar, China BioMedicine (CBM), and China National Knowledge Infrastructure (CNKI) databases from their inception through August 1st, 2013. A meta-analysis was then performed using the STATA 12.0 software. The crude odds ratios (OR) with 95% confidence intervals (CI) were calculated.

RESULTS

Eleven case-control studies were included with a total of 10,252 subjects, including 5429 MI patients and 4823 healthy controls. Our meta-analysis results indicated that IL-6 -174 G/C polymorphism may increase the risk of MI (C allele vs. G allele: OR=1.07, 95% CI: 1.01-1.14, p=0.018; GC+CC vs. GG: OR=1.14, 95% CI: 1.04-1.24, p=0.003; respectively). However, our results showed no significant association between IL-6 -572 G/C polymorphism and MI risk (C allele vs. G allele: OR=0.88, 95% CI: 0.75-1.03, p=0.098; GC+CC vs. GG: OR=0.87, 95% CI: 0.70-1.07, p=0.173; respectively). No publication bias was detected in this meta-analysis.

CONCLUSION

The current meta-analysis suggests that IL-6 -174 G/C polymorphism may contribute to MI susceptibility. Thus, detection of IL-6 -174 G/C polymorphisms may be a promising biomarker for the early detection of MI. However, IL-6 -572 G/C polymorphism may not associate with the risk of MI.

Influence of interleukin-6 gene -174G>C polymorphism on development of atherosclerosis: a meta-analysis of 50 studies involving 33,514 subjects

Increasing epidemiological studies have focused on the associations between interleukin-6 (IL-6) gene -174G>C polymorphism and atherosclerotic diseases, but the results are still controversial. This meta-analysis was designed to identify whether this association exists. PubMed, Embase, Web of Science, Cochrane database, Clinicaltrials.gov and Current Controlled Trials, Chinese Clinical Trial Registry, CBMdisc, CNKI and Google Scholar were searched to get the genetic association studies. The crude odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were used to estimate the association between the IL-6 gene -174G>C polymorphism and atherosclerosis ( AS ) risk. The subgroup analyses were made on the following: ethnicity, atherosclerotic diseases and source of controls. Finally, 50 studies (15,029 cases and 18,485 controls) were included in this meta-analysis. Overall, no significant association was found between the IL-6 gene -174G>C polymorphism and AS risk (for C allele vs. G allele: OR=1.02, 95% CI=0.94-1.11, p=0.64; for C/C vs. G/G: OR=1.01, 95% CI=0.85-1.21, p=0.88; for C/C vs. C/G+G/G: OR=0.97, 95% CI=0.84-1.12, p=0.68; for C/C+C/G vs. G/G: OR=1.07, 95% CI=0.97-1.17, p=0.18). In the subgroup analyses, significant associations were found between the IL-6 gene -174G>C polymorphism and AS in non-Caucasian group (for CC+CG vs. GG: OR=1.22, 95% CI=1.06-1.41, p=0.005), other atherosclerotic diseases group (for C allele vs. G allele: OR =0.75, 95% CI=0.61-0.93, p=0.008; for C/C vs. G/G: OR=0.56, 95% CI=0.38-0.81, p=0.002; for C/C vs. C/G+G/G: OR=0.60, 95% CI=0.45-0.79, p=0.0004) and population-based group (for C allele vs. G allele: OR=1.09, 95% CI=1.00-1.18, p=0.04; for CC+CG vs. GG: OR=1.15, 95% CI=1.04-1.27, p=0.005). In summary, the present meta-analysis suggests that the IL-6 gene -174G C polymorphism is associated with the susceptibility to AS. However, due to the high heterogeneity in the meta-analysis, the results should be interpreted with caution.

Association between interleukin 6 and interleukin 16 gene polymorphisms and coronary heart disease risk in a Chinese population

OBJECTIVE

To investigate the role of interleukin 6 (IL6) and IL16 single nucleotide polymorphisms (SNPs) in coronary artery disease (CAD) risk in a Chinese population.

METHODS

Patients with CAD and healthy control subjects were recruited. IL6 (rs1800795 and rs1800796) and IL16 (rs8034928, rs3848180, rs4577037, rs1131445, rs4778889 and rs11556218) genotyping was performed on the MassARRAY® platform (Sequenom®, San Diego, CA, USA).

RESULTS

Frequencies of rs8034928 variant C allele and rs11556218 variant T allele were higher in patients with CAD (n = 326) than controls (n = 341). The rs8034928 C/C genotype (odds ratio [OR] 2.03; 95% confidence intervals [CI] 1.16, 3.62) and C allele (OR 1.97; 95%CI 1.15, 3.45) were associated with increased risk of CAD compared with wild type. Similarly, the rs11556218 T/T genotype (OR 2.44; 95%CI 1.15, 5.44) and T allele (OR 2.37; 95%CI 1.13, 5.24) were associated with increased CAD risk compared with wild type.

CONCLUSION

The SNPs rs8034928 and rs11556218 are associated with CAD risk in the Chinese population, and may be useful predictive markers for CAD susceptibility.

Pro-inflammatory genetic profile and familiarity of acute myocardial infarction

Background

Acute myocardial infarction (AMI) is a multifactorial disease with a complex pathogenesis where lifestyle, individual genetic background and environmental risk factors are involved. Altered inflammatory responses are implicated in the pathogenesis of atherosclerosis and a premature AMI of parents is associated with an increased risk of the disease in their offspring (Offs). However, the genetic background of familiarity for AMI is still largely unknown. To understand which genes may predispose to increased risk of cardiovascular disease gene polymorphism of immune regulatory genes, and clinical events from the Offs of parents with an early AMI were investigated. Genetics data from Offs were compared with those obtained from healthy subjects and an independent cohort of patients with clinical sporadic AMI. Rates of clinical events during a 24 years follow up from Offs and from an independent Italian population survey were also evaluated.

Results

This study showed that a genetic signature consisting of the concomitant presence of the CC genotype of VEGF, the A allele of IL-10 and the A allele of IFN-γ was indeed present in the Offs population. In fact, the above genetic markers were more frequent in unaffected Offs (46.4%) and patients with sporadic AMI (31.8%) than in the CTR (17.3%) and the differences were highly statistically significant (Offs vs CTR: p = 0.0001, OR = 4.129; AMI vs CTR: p = 0.0001, OR = 2.224). During the 24-year follow-up, Offs with a positive familiarity in spite of a relatively young age showed an increased prevalence of diabetes, ischemic heart disease and stroke. These findings reinforce the notion that subjects with a familial history of AMI are at risk of an accelerated aging of cardiovascular system resulting in cardiovascular events.

Conclusion

Our data suggest that selected genes with immune regulatory functions are part of the complex genetic background contributing to familiarity for cardiovascular diseases. This inflammatory genetic profile, along with classical cardiovascular risk factors, may be used for better defining individual risk of AMI in unaffected subjects.

Association of interleukin-6 circulating levels with coronary artery disease: a meta-analysis implementing mendelian randomization approach

BACKGROUND

We aim to investigate whether the association between circulating interleukin 6 (IL-6) levels and the risk for coronary artery disease (CAD) is robust and perhaps even causal by a meta-analysis implementing mendelian randomization approach with IL-6 gene G-174C polymorphism as an instrument.

METHODS

Data were available from 19 articles encompassing 9417 CAD patients and 15982 controls. A random effects model was applied irrespectively of between-study heterogeneity, and publication bias was examined using a funnel plot and the corresponding statistics.

RESULTS

Overall, comparison of IL-6 gene alleles -174C with -174G had 4% increased risk for CAD (95% confidence interval [95% CI]: 0.97-1.10; P=0.285), accompanying marginal heterogeneity (I(2)=38.3%; P=0.033). This association was potentiated in dominant model as odds ratio (OR) reached 1.08 (95% CI: 0.96-1.22; P=0.204) and heterogeneity was significant (I(2)=58.4%; P<0.0005). Subgroup analysis by ethnicity indicated that carriers of -174C allele were associated with a 12% increased risk for CAD in prospective studies involving White populations (OR=1.12; 95% CI: 0.95-1.33; P=0.184), whereas the association in East Asians was remarkably reversed with 37-46% reduced risk. Relative to -174GG homozygotes, carriers of -174C allele had an overall 0.24 pg/ml high circulating IL-6 levels (P=0.047). The predicted OR for 1 pg/ml elevation in IL-6 levels was 1.60 (95% CI: 1.44-1.72; P<0.01) in prospective studies involving White populations. Publication biases were absent for all comparisons (P>0.1).

CONCLUSION

Our findings provided strong evidence on the causal association of circulating IL-6 levels with the development of CAD in White populations.

Lack of association between IL-1 and IL-6 gene polymorphisms and myocardial infarction in Turkish population

Inflammation and genetics play a key role in the pathogenesis of atherosclerosis and its clinical result myocardial infarction (MI). Proinflammatory cytokines, IL-1 and IL-6, have been shown to play essential roles in developmental stages of coronary artery plaque formation. The aim of this study was to determine the association between IL-1 [IL-1RN, IL-1β (-511, +3953)], IL-6 [-174, -572, -597] gene polymorphisms and MI in Turkish population. A total of 402 people were participated; 235 healthy control subjects and 167 MI patients (MI<40, n: 72; MI>40, n: 95). Polymerase chain reaction (PCR) was used to determine the genotype of IL-1RN, whereas the genotypes of IL-1β (-511, +3953) and IL-6 (-174, -572, -597) were determined using PCR followed with restriction digestion analysis. There was no significant difference between MI and controls for IL-1RN, IL-1β-511, +3953 (P: 0.875, 0.608, 0.442) and IL-6 -174, -572, -597 (P: 0.977, 0.632, 0.584) gene polymorphisms. Lack of association was observed between MI at younger age (MI<40) and either IL-1RN VNTR, IL-1β-511, +3953 (P: 0.878, 0.732, 0.978) or IL-6 -174, -572, -597 (P: 0.313, 0.654, 0.552) gene polymorphisms. This study demonstrated that there was not any association between IL-1, IL-6 gene variants and MI in Turkish population. In addition, IL-1 and IL-6 gene polymorphisms did not affect MI at younger age (MI<40) or older age (MI>40). Thus, IL-1 and IL-6 single nucleotide polymorphisms may not be a risk factor for susceptibility to MI in Turkish population.

Inflammatory gene variants in the Tsimane, an indigenous Bolivian population with a high infectious load

The Tsimane of lowland Bolivia are an indigenous forager-farmer population living under conditions resembling pre-industrial European populations, with high infectious morbidity, high infection and inflammation, and shortened life expectancy. Analysis of 917 persons ages 5 to 60+ showed that allele frequencies of 9 SNPs examined in the apolipoprotein E (apoE), C-reactive protein (CRP), and interleukin-6 (IL-6) genes differed from some European, African, and north Asian-derived populations. The apoE2 allele was absent, whereas four SNPs related to CRP and IL-6 were monomorphic: CRP (rs1800947, rs3093061, and rs3093062) and IL-6 (rs1800795). No significant differences in apoE, CRP, and IL-6 variants across age were found CRP levels were higher in carriers of two CRP proinflammatory SNPs, whereas they were lower in carriers of apoE4. Taken together the evidence for (1) different allele frequencies between the Tsimane and other populations and (2) the correlations of CRP and apoE alleles with blood CRP may suggest that these variants are under selection in response to a high infection environment.

Genetic determinants of osteoporosis: common bases to cardiovascular diseases?

Osteoporosis is the most common and serious age-related skeletal disorder, characterized by a low bone mass and bone microarchitectural deterioration, with a consequent increase in bone fragility and susceptibility to spontaneous fractures, and it represents a major worldwide health care problem with important implications for health care costs, morbidity and mortality. Today is well accepted that osteoporosis is a multifactorial disorder caused by the interaction between environment and genes that singularly exert modest effects on bone mass and other aspects of bone strength and fracture risk. The individuation of genetic factors responsible for osteoporosis predisposition and development is fundamental for the disease prevention and for the setting of novel therapies, before fracture occurrence. In the last decades the interest of the Scientific Community has been concentrated in the understanding the genetic bases of this disease but with controversial and/or inconclusive results. This review tries to summarize data on the most representative osteoporosis candidate genes. Moreover, since recently osteoporosis and cardiovascular diseases have shown to share common physiopathological mechanisms, this review also provides information on the current understanding of osteoporosis and cardiovascular diseases common genetic bases.

Management of cardiovascular complications in systemic lupus erythematosus

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Patients with SLE have an excess risk compared with the general population; this is particularly pronounced in younger women with SLE who have an excess risk of over 50-fold compared with population controls. There is a higher prevalence of subclinical atherosclerosis in patients with SLE compared with controls, as demonstrated by a variety of imaging modalities discussed in this review. The causality of the excess risk of CVD and subclinical atherosclerosis is multifactorial in patients with SLE. While traditional risk factors play a role, after controlling for the traditional Framingham risk factors, the excess risk is still 7.5-fold greater than the general population. This review will also cover novel cardiovascular risk factors and some SLE-specific variables that contribute to CVD risk. This review discusses the risk factor modification and the evidence available for treatment of these risk factors in SLE. There have not yet been any published randomized, controlled trials in patients with SLE with respect to CVD risk factor modifications. Thus, the treatment and management recommendations are based largely on published guidelines for other populations at high risk for CVD.

The relationship of the interleukin-6 -174 G>C gene polymorphism with cardiovascular risk factors in Turkish polycystic ovary syndrome patients

We aimed to evaluate the relationship between 174 promoter region of the interleukin-6 (IL-6) C/G gene polymorphism and high sensitive C-reactive protein (hs-CRP), fibrinogen and carotis intima-media thickness (CIMT), body mass index, homeostatic model assessment (HOMA) insulin resistance index, serum lipid parameters, in polycystic ovary syndrome (PCOS) patients carrying a potential risk for developing cardiovascular disease (CVD). We studied 88 PCOS patients and 119 healthy controls. PCOS was defined by the Rotterdam PCOS consensus criteria. The genotype IL-6 distribution did differ between the control group (CC 10.1%, GC 63.0%, GG 29.6%) and the PCOS patients (CC 5.7%, GC 29.5%, GG 64.8%) (P < 0.001). The frequency of the polymorphic G allele was also no similar for the group with PCOS as for the control group with 79.5% and 58.4% respectively (P < 0.001). Both in PCOS patients and in control group, no statistically significant difference was determined between C/C, G/C and G/G, and blood cholesterol levels, triglyceride levels, high-density lipoprotein levels, low density lipoprotein levels, fasting blood sugar levels, insulin levels, HOMA values, CIMT measurements either on the right or left side, hs-CRP, f-testosterone, fibrinogen and 17 alpha-hydroxy-progesterone levels (P > 0.05). Gene polymorphism of IL-6 -174 G>C is a risk factor for PCOS in Turkish patients, but we found no relationship between the cardiovascular risk factors and IL-6 -174 G>C gene polymorphism in women with PCOS and healthy subjects. Our negative results in risk factors of CVD can probably be explained by the fact that metabolic parameters and endothelial systems of patients may not yet be affected in this short time of period.

Inflammation in aging part 1: physiology and immunological mechanisms

During the aging process, remodeling of several body systems occurs, and these changes can have a startling effect upon the immune system. The reduction in sex steroids and growth hormones and declines in vitamin D concentration that accompany the aging process are associated with increases in the baseline levels of inflammatory proteins. At the same time, inflammation arising from atherosclerosis and other chronic diseases further contributes to the inflammatory milieu and effects a state of chronic inflammation. This chronic inflammation, or ''inflammaging'' as it has been termed, seems to be associated with a host of adverse effects contributing to many of the health problems that increase morbidity and decrease both quality of life and the ability to maintain independence in old age. For nurses to be truly informed when caring for older people and to ensure that they have a detailed understanding of the complexities of older people's health needs, they must have a knowledge of the physiological and immunological changes with age. This is the first of a two-part article on inflammatory processes in aging. These age-related changes are presented here, including an examination of the impact of genetic and lifestyle factors. The effect of these changes on the health of the individual and implications for practice are described in Part 2.

Accelerated atherosclerosis, arterial thromboembolism, and preventive strategies in systemic lupus erythematosus

With improved disease survival, arterial thromboembolism has become an important cause of morbidity in patients with systemic lupus erythematosus (SLE). A number of conventional and non-conventional risk factors are associated with accelerated atherosclerosis. Regular surveillance and control of traditional risk factors is mandatory, and so is the appropriate use of the statins, anti-malarial agents, anti-platelet agents, and anti-coagulation for primary and secondary prevention of arterial thromboembolism in SLE patients. Judicious use of corticosteroids, calcineurin inhibitors, hormonal replacement therapy, and the cyclooxygenase 2 inhibitors is equally important.

Influence of interleukin-6 G-174C gene polymorphism on coronary artery disease, cardiovascular complications and mortality in dialysis patients

BACKGROUND

Inflammation is a well recognized central component of atherosclerotic processes in chronic kidney disease. Interleukin-6 (IL-6) levels are a strong determinant of cardiovascular mortality in dialysis patients. We evaluated the impact of IL-6 gene G-174C polymorphism associated with modified IL-6 production on the development of coronary artery disease (CAD), cardiovascular events and mortality in chronic dialysis patients.

METHODS

We studied n = 463 patients on chronic dialysis with angiographically confirmed (n = 218) or excluded (n = 245) CAD followed up for 65 months after initiation of dialysis. Monitored were arterial hypertension, diabetes mellitus, hyperlipidemia, smoking, CRP and fibrinogen. IL-6 gene G-174C polymorphism was determined by PCR amplification.

RESULTS

The CC genotype was associated with an impaired patient survival (p < 0.05) remaining an independent risk factor for death in multivariate analysis (HR for CC genotype: 3.58, CI: 1.41-9.07, p < 0.01). CC genotype carrying CAD patients suffered significant frequently cardiovascular events (revascularization, myocardial infarction, death) compared to GG/GC genotype carriers (85.2% vs. 66.5, p < 0.05). However, the IL-6 gene G-174C polymorphism was not related to the onset and development of CAD itself (ns) and the inflammation parameters CRP and fibrinogen did not differ between the genotypes under investigation (ns).

CONCLUSIONS

Our results suggest that IL-6 gene G-174C polymorphism is associated with the incidence of cardiovascular events and mortality in chronic dialysis patients.

Polymorphism in the IL6 promoter region is associated with the risk factors and markers of subclinical atherosclerosis in men: The Cardiovascular Risk in Young Finns Study

OBJECTIVE

Inflammatory factors modify the risk of coronary heart disease. Promoter region genetic polymorphism of inflammatory cytokine interleukin-6 (IL6 -174 G>C) is associated with the variation of IL-6 production. We investigated whether IL6 -174 G>C associates with the risk factors of atherosclerosis and carotid artery compliance (CAC) in young subjects.

METHODS AND RESULTS

As part of the Cardiovascular Risk in Young Finns Study, we performed carotid artery ultrasound examinations, IL6 -174 G>C genotyping and coronary heart disease risk factor determination for 2228 subjects aged 24-39 years. In men CAC was higher for IL6 -174 GG (2.10+/-0.65) than for GC (2.00+/-0.68) or CC (1.95+/-0.63, %/10mmHg, mean+/-S.D., p=0.0221). A similar association was observed for HDL cholesterol (GG 1.22+/-0.29, GC 1.15+/-0.27 and CC 1.14+/-0.28mmol/L, p=0.0015) and apolipoprotein A1 (apoA1) (GG 1.44+/-0.21, GC 1.40+/-0.20, CC 1.38+/-0.21mmol/L, p=0.0118). The opposite genotype effect was present in systolic (GG 127+/-13.1, GC 129+/-13.1, CC 130+/-14.3mmHg, p=0.0382) and diastolic blood pressure (GG 73.8+/-9.14, GC 75.1+/-8.68, CC 75.9+/-9.70mmHg, p=0.0374). The genetic effect size for these parameters was not significant in women.

CONCLUSIONS

IL6 -174 allele G homozygozity associates with beneficial profile of early predictors of atherosclerosis such as high CAC, HDL-C and apoA1 as well as low systolic and diastolic blood pressure in men.

The relationship of the interleukin-6 -174 G>C gene polymorphism with oxidative stress markers in Turkish polycystic ovary syndrome patients

OBJECTIVE

Interleukin-6 (IL-6) is a key pro-inflammatory and immune-modulatory cytokine of relevance for cardiovascular (CD) diseases. Cardiovascular risk factors that have been reported include oxidative stress markers [nitric oxide (NO), malondialdehyde (MDA), disulphite (SH)]. We aimed to evaluate the relation between the IL-6 G/C gene polymorphism and oxidative stress markers in polycystic ovary syndrome (PCOS) patients.

DESIGN AND PATIENTS

We studied 85 PCOS patients and 115 healthy controls. PCOS was defined by the Rotterdam PCOS consensus criteria.

RESULTS

The genotype IL-6 distribution did differ between the control group (CC 9.6%, GC 63.4%, GG 27.0%) and the PCOS patients (CC 4.7%, GC 29.4%, GG 65.9%) (p<0.001). The frequency of the polymorphic G allele was also not similar for the group with PCOS as for the control group with 80.6% and 58.7%, respectively (p<0.001). No statistically significant difference was determined for MDA and NO levels in PCOS patients and control group (p>0.05). Only SH levels were found to be high in favor of patient group (p<0.05). No statistically significant difference was determined between IL-6 G/C gene polymorphism and oxidative stress markers in PCOS patients and in the control group.

CONCLUSION

Gene polymorphism of IL-6 -174 G>C is a risk factor for PCOS in Turkish patients. IL-6 gene polymorphisms are not related to NO, MDA, and SH levels in PCOS. Our negative results in risks factors of CV disorders can probably be explained by the fact that metabolic parameters and endothelial systems of patients may not yet be affected in this short period of time.

Common studied polymorphisms do not affect plasma cytokine levels upon endotoxin exposure in humans

The aim of this study was to investigate to what extent single nucleotide polymorphisms (SNPs) in promoter regions of genes of Toll-like receptor (TLR)-4, tumour necrosis factor (TNF)-alpha, interleukin (IL)-18, interferon (IFN)-gamma, IL-6 and IL-10 affect the cytokine response during a controlled low-grade inflammatory response in vivo. Two hundred healthy young male volunteers were genotyped, and cytokine levels were measured in response to a low-dose intravenous bolus of Escherichia coli endotoxin. No association was detected between SNPs (TLR-4299, TLR-4399, TNF-308, IL-18-137, IL-18-607, IFN-gamma+874, IL-6-174, IL-10-592 and IL-10-1082) and endotoxin-induced changes in plasma levels of TNF-alpha, IL-6 and IL-10. IL-18 levels were unaffected by endotoxin. In conclusion, the investigated SNPs did not affect endotoxin-induced low-grade cytokine production of TNF-alpha, IL-6, IL-18 or IL-10 in healthy young men. Previous reports of a major heritability factor in the inflammatory response may be due to other target genes or effects in older age groups or women.

Genetic polymorphisms of the RAS-cytokine pathway and chronic kidney disease

Chronic kidney disease (CKD) in children is irreversible. It is associated with renal failure progression and atherosclerotic cardiovascular (CV) abnormalities. Nearly 60% of children with CKD are affected since birth with congenital or inherited kidney disorders. Preliminary evidence primarily from adult CKD studies indicates common genetic risk factors for CKD and atherosclerotic CV disease. Although multiple physiologic pathways share common genes for CKD and CV disease, substantial evidence supports our attention to the renin angiotensin system (RAS) and the interlinked inflammatory cascade because they modulate the progressions of renal and CV disease. Gene polymorphisms in the RAS-cytokine pathway, through altered gene expression of inflammatory cytokines, are potential factors that modulate the rate of CKD progression and CV abnormalities in patients with CKD. For studying such hypotheses, the cooperative efforts among scientific groups and the availability of robust and affordable technologies to genotype thousands of single nucleotide polymorphisms (SNPs) across the genome make genome-wide association studies an attractive paradigm for studying polygenic diseases such as CKD. Although attractive, such studies should be interpreted carefully, with a fundamental understanding of their potential weaknesses. Nevertheless, whole-genome association studies for diabetic nephropathy and future studies pertaining to other types of CKD will offer further insight for the development of targeted interventions to treat CKD and associated atherosclerotic CV abnormalities in the pediatric CKD population.

IL-6 gene variation is associated with IL-6 and C-reactive protein levels but not cardiovascular outcomes in the Cardiovascular Health Study

Interleukin-6 (IL-6) and C-reactive protein (CRP) levels increase with age and likely play a role in adverse health outcomes in older adults. The relationship between IL-6 gene tag single nucleotide polymorphisms (SNPs) and circulating IL-6 and CRP levels, cardiovascular disease (CVD) outcomes, and mortality in Caucasian (CA) and African American (AA) participants of the Cardiovascular Health Study (CHS) was evaluated using ANCOVA and Cox proportional hazards models. The minor allele of the promoter SNP 1510 and intronic SNP 3572 associates with significantly higher serum IL-6 and CRP levels in CA but not AA. The CRP association persisted after CA and AA populations were combined and after accounting for multiple comparisons. These associations did not carry through to cardiovascular disease outcomes. Decreased risk of stroke was identified in CA, with the minor allele of SNP 1111 (HRR 0.71, 95% CI 0.52, 0.95), P = 0.02, and increased risk of CVD and all-cause mortality (HRR 1.31, 95% CI 1.05-1.64) in AAs heterozygote for SNP 2989. While genetic variation in the IL-6 gene was associated with circulating IL-6 and especially with CRP concentrations in this study, there is little evidence for association between common IL-6 gene variation and adverse health outcomes in this population of older adults.

C-Reactive Protein Gene Polymorphisms, C-Reactive Protein Blood Levels, and Cardiovascular Disease Risk

C-reactive protein (CRP), a blood marker of inflammation and a hallmark of the acute-phase response, has been shown to be a powerful and specific predictor of cardiovascular event risk in populations of otherwise healthy persons. Here we review what is known about CRP gene polymorphisms, discuss how these might affect the epidemiology of CRP and our understanding of CRP's contribution to cardiovascular disease, and examine their potential clinical usefulness. Evidence shows that certain subtle variations in the CRP gene sequence, mostly single nucleotide polymorphisms, predictably and strongly influence the blood level of CRP. Some of these variations are associated with clinical correlates of cardiovascular disease. If future studies can establish with certainty that CRP influences cardiovascular biology, then CRP gene profiling could have clinical utility.

Additive effect of interleukin-6 and C-reactive protein (CRP) single nucleotide polymorphism on serum CRP concentration and other cardiovascular risk factors

BACKGROUND

Serum C-reactive protein (CRP) levels, closely associated with cardiovascular disease (CVD) risk are influenced by CRP or interleukin-6 (IL-6) single nucleotide polymorphism (SNPs). However, it is still controversial. Therefore, we investigated the association of IL-6/CRP SNPs and serum CRP levels or other CVD risk factors in healthy adult Korean men.

METHODS

In healthy adult men (age>or=20 years, n=677), we genotyped IL-6-572C>G and CRP SNPs (-717G>A, 1444C>T, 2147A>G) and measured anthropometric parameters, lipid profile, serum levels of CRP and IL-6 and insulin resistance.

RESULTS

At IL-6-572C>G (n=677), subjects with G/G genotype (n=42) showed higher concentrations of CRP (P=0.027) and IL-6 (P=0.028) as compared with C allele carriers after age-adjustment (C/C: n=371, C/G: n=264). Fasting insulin and homeostatis model assessment insulin resistance (HOMA-IR) were also higher in G/G genotype. However, there were no significant differences in other metabolic biomarkers. Among 677 study subjects, 676 were genotyped at CRP-717G>A (G/G: n=513, G/A: n=150, A/A: n=13), 672 at CRP+1444C>T (C/C: n=580, C/T: n=85, T/T: n=7), and 668 at CRP+2147A>G (A/A: n=273, A/G: n=296, G/G: n=99). There were no significant differences in CRP concentrations and other markers related to CVD risk according to each CRP SNP genotype. However, we could find the additive gene-gene interaction between IL-6-572C>G and CRP SNPs on CRP concentration; subjects with the 'G/G' at IL-6-572 showed the highest CRP levels when they have variant allele at CRP SNPs after adjusted for age, body mass index, cigarette smoking and alcohol drinking (-717G>A: F=7.806, P=0.005; CRP+1444C>T: F=8.398, P=0.004; and CRP+2147A>G: F=7.564, P=0.006, respectively) Particularly, G allele carriers at CRP+2147A>G in subjects with IL-6-572G/G showed highest HOMA-IR (F=9.092, P=0.003).

CONCLUSION

The present data showed that serum CRP levels and other CVD risk factors appeared more influenced by IL-6-572C>G rather than CRP SNPs (-717G>A, 1444C>T, and 2147A>G), however CRP levels and insulin resistance may be additively affected by IL-6-572 and CRP SNP, particularly when subjects with G/G genotype at IL-6-572 have allele variant at CRP SNPs.

Genetics and heritability of coronary artery disease and myocardial infarction

A positive family history is frequently reported by patients with coronary artery disease (CAD) or myocardial infarction. For risk stratification, it is crucial to distinguish between accidental reoccurrence of sporadic cases and cases with a true heritable component of the conditions. A familial predisposition is assumed when a myocardial infarction is diagnosed by a male first degree relative before the 55th year of life or a female first degree relative before the 65th year of life. The current manuscript reviews major studies from which a familial risk of CAD or myocardial infarction can be inferred. Moreover, a brief overview summarizes the current results of molecular genetic research on chromosomal loci and genes relevant for CAD and myocardial infarction.