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Bongani M Mayosi

Publications and source records attributed to Bongani M Mayosi.

At least 19 recordsLinked to original sources
PubMed2006

Association between aldosterone production and variation in the 11beta-hydroxylase (CYP11B1) gene.

CONTEXT: Variation in the region of chromosome 8 including the genes steroid 11beta-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) influences mineralocorticoid and glucocorticoid metabolism. However, the relative importance of polymorphisms in CYP11B1 and CYP11B2 in determining these phenotypes is unknown. OBJECTIVE: Our objective was to investigate genetic influences of the CYP11B1 and CYP11B2 genes on mineralocorticoid metabolism. DESIGN: We measured 24-h urinary excretion of the key metabolites of the principal mineralocorticoids, glucocorticoids and androgens secreted by the adrenal cortex. We genotyped polymorphisms spanning the CYP11B1 and CYP11B2 genes, which together capture all common variations at the locus. PARTICIPANTS: Participants included 573 members of 105 British Caucasian families ascertained on a hypertensive proband. MAIN OUTCOME MEASURES: We assessed heritability of urinary tetrahydroaldosterone (THAldo) excretion and association of THAldo excretion with genotype. RESULTS: The heritability of THAldo excretion was 52% (P < 10(-6)). There was significant association between THAldo and genotype at several of the CYP11B1/B2 polymorphisms. The strongest association was observed at the rs6387 (2803A/G) polymorphism in intron 3 of CYP11B1 (P = 0.0004). Association followed a codominant model with a 21% higher THAldo excretion per G allele. Genotype at rs6387 accounted for 2.1% of the total population variability of THAldo. We found significant association between THAldo excretion and urinary total androgen excretion, urinary tetrahydrodeoxycortisol level, and urinary cortisol metabolites (all P < 0.001). CONCLUSIONS: Aldosterone synthesis is highly heritable and is affected by genotype at CYP11B1. Our findings support the hypothesis that genetically determined differences in 11-hydroxylation efficiency can have downstream effects on mineralocorticoid synthesis. Such effects may be of relevance to the development of low-renin essential hypertension.

Aldosterone↗
PubMed2006

Arrhythmogenic right ventricular cardiomyopathy type 6 (ARVC6): support for the locus assignment, narrowing of the critical region and mutation screening of three candidate genes.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a heritable disorder characterized by progressive degeneration of right ventricular myocardium, arrhythmias and an increased risk of sudden death at a young age. By linkage analysis, ARVC type 6 was previously mapped to a 10.6 cM region on chromosome 10p12-p14 in a large North American kindred. To date, the genetic defect that causes ARVC6 has not been identified. METHODS: We identified a South African family of 13 members with ARVC segregating as an autosomal dominant disorder. The diagnosis of ARVC was based on international diagnostic criteria. All available family members were genotyped with microsatellite markers at six known ARVC loci, and positional candidate gene screening was performed. RESULTS: Genetic linkage and haplotype analysis provided lod scores that are highly suggestive of linkage to the ARVC6 locus on chromosome 10p12-p14, and the narrowing of the critical region to approximately 2.9 Mb. Two positional candidate genes (ITG8 and FRMD4A) were screened in which defects could possibly disrupt cell-cell adhesion. A non-positional candidate gene with apoptosis inducing properties, LAMR1P6 (laminin receptor 1 pseudogene 6) was also screened. Direct sequencing of DNA from affected individuals failed to detect disease-causing mutations in the exonic sequences of the three genes investigated. CONCLUSION: The narrowing of the ARVC6 critical region may facilitate progress towards the identification of the gene that is involved in ARVC. Identification of the causative genes for ARVC will contribute to the understanding of the pathogenesis and management of this poorly understood condition.

Adolescent↗
PubMed2006

Clinical characteristics and initial management of patients with tuberculous pericarditis in the HIV era: the Investigation of the Management of Pericarditis in Africa (IMPI Africa) registry.

BACKGROUND: The incidence of tuberculous pericarditis has increased in Africa as a result of the human immunodeficiency virus (HIV) epidemic. However, the effect of HIV co-infection on clinical features and prognosis in tuberculous pericarditis is not well characterised. We have used baseline data of the Investigation of the Management of Pericarditis in Africa (IMPI Africa) registry to assess the impact of HIV co-infection on clinical presentation, diagnostic evaluation, and treatment of patients with suspected tuberculous pericarditis in sub-Saharan Africa. METHODS: Consecutive adult patients in 15 hospitals in three countries in sub-Saharan Africa were recruited on commencement of treatment for tuberculous pericarditis, following informed consent. We recorded demographic, clinical, diagnostic and therapeutic information at baseline, and have used the chi-square test and analysis of variance to assess probabilities of significant differences (in these variables) between groups defined by HIV status. RESULTS: A total of 185 patients were enrolled from 01 March 2004 to 31 October 2004, 147 (79.5%) of whom had effusive, 28 (15.1%) effusive-constrictive, and 10 (5.4%) constrictive or acute dry pericarditis. Seventy-four (40%) had clinical features of HIV infection. Patients with clinical HIV disease were more likely to present with dyspnoea (odds ratio [OR] 3.2, 95% confidence interval [CI] 1.4 to 7.4, P = 0.005) and electrocardiographic features of myopericarditis (OR 2.8, 95% CI 1.1 to 6.9, P = 0.03). In addition to electrocardiographic features of myopericarditis, a positive HIV serological status was associated with greater cardiomegaly (OR 3.89, 95% CI 1.34 to 11.32, P = 0.01) and haemodynamic instability (OR 9.68, 95% CI 2.09 to 44.80, P = 0.0008). However, stage of pericardial disease at diagnosis and use of diagnostic tests were not related to clinical HIV status. Similar results were obtained for serological HIV status. Most patients were treated on clinical grounds, with microbiological evidence of tuberculosis obtained in only 13 (7.0%) patients. Adjunctive corticosteroids were used in 109 (58.9%) patients, with patients having clinical HIV disease less likely to be put on them (OR 0.37, 95% CI 0.20 to 0.68). Seven patients were on antiretroviral drugs. CONCLUSION: Patients with suspected tuberculous pericarditis and HIV infection in Africa have greater evidence of myopericarditis, dyspnoea, and haemodynamic instability. These findings, if confirmed in other studies, may suggest more intensive management of the cardiac disease is warranted in patients with HIV-associated pericardial disease.

Adolescent↗
PubMed2006

How strong is the evidence for use of beta-blockers as first-line therapy for hypertension? Systematic review and meta-analysis.

OBJECTIVE: To quantify the effect of first-line antihypertensive treatment with beta-blockers on mortality, morbidity and withdrawal rates, compared with the other main classes of antihypertensive agents. METHODS: We identified eligible trials by searching the Cochrane Controlled Trials Register, Medline, Embase, reference lists of previous reviews, and contacting researchers. We extracted data independently in duplicate and conducted meta-analysis by analysing trial participants in groups to which they were randomized, regardless of subsequent treatment actually received. RESULTS: Thirteen trials with 91,561 participants, meeting inclusion criteria, compared beta-blockers to placebo (four trials; n = 23,613), diuretics (five trials; n = 18,241), calcium-channel blockers (CCBs) (four trials; n = 44,825), and renin-angiotensin system (RAS) inhibitors, namely angiotensin-converting enzyme inhibitors or angiotensin receptor blockers (three trials; n = 10,828). Compared to placebo, beta-blockers reduced the risk of stroke (relative risk 0.80; 95% confidence interval 0.66-0.96) with a marginal fall in total cardiovascular events (0.88, 0.79-0.97), but did not affect all-cause mortality (0.99, 0.88-1.11), coronary heart disease (0.93, 0.81-1.07) or cardiovascular mortality (0.93, 0.80-1.09). The effect on stroke was less than that of CCBs (1.24, 1.11-1.40) and RAS inhibitors (1.30, 1.11-1.53), and that on total cardiovascular events less than that of CCBs (1.18, 1.08-1.29). In addition, patients on beta-blockers were more likely to discontinue treatment than those on diuretics (1.80; 1.33-2.42) or RAS inhibitors (1.41; 1.29-1.54). CONCLUSION: Beta-blockers are inferior to CCBs and to RAS inhibitors for reducing several important hard end points. Compared with diuretics, they had similar outcomes, but were less well tolerated. Hence beta-blockers are generally suboptimal first-line antihypertensive drugs.

Adrenergic beta-Antagonists↗
PubMed2005

Epidemiology and etiology of cardiomyopathy in Africa.

BACKGROUND: Cardiomyopathy, an often irreversible form of heart muscle disease that is associated with a dismal outcome, is endemic in Africa. The primary objective of this review was to summarize the current state of knowledge on the epidemiology and etiology of cardiomyopathy in people living in Africa and to identify new avenues for research. METHODS AND RESULTS: We searched MEDLINE (January 1, 1966, through February 12, 2005) and reference lists of articles for relevant references. Unlike other parts of the world in which cardiomyopathy is rare, dilated cardiomyopathy is a major cause of heart failure throughout Africa. Similarly, peripartum cardiomyopathy is ubiquitous on the continent, with an incidence ranging from 1 in 100 to 1 in 1000 deliveries. There is an apparent marked regional variation in the pathogenesis of dilated cardiomyopathy and peripartum cardiomyopathy, underlining the heterogeneity of causative factors in these conditions. By contrast, endomyocardial fibrosis is restricted to the tropical regions of East, Central, and West Africa. Although the pathogenesis of endomyocardial fibrosis is not fully understood, it seems that the conditioning factors are geography and diet, the triggering factor may be an as yet unidentified infective agent, and the perpetuating factor is eosinophilia. Although epidemiological studies are lacking, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy seem to have characteristics similar to those of other populations elsewhere in the world. CONCLUSIONS: There is a need for large-scale epidemiological studies of the incidence, prevalence, determinants, and outcome of cardiomyopathy in Africa to inform strategies for the treatment and prevention of heart muscle disease on the continent.

Africa↗
PubMed2005

Tuberculous pericarditis.

BACKGROUND: The incidence of tuberculous pericarditis is increasing in Africa as a result of the human immunodeficiency virus (HIV) epidemic. The primary objective of this article was to review and summarize the literature on the pathogenesis, diagnosis, and management of tuberculous pericarditis. METHODS AND RESULTS: We searched MEDLINE (January 1966 to May 2005) and the Cochrane Library (Issue 1, 2005) for information on relevant references. A "definite" diagnosis of tuberculous pericarditis is based on the demonstration of tubercle bacilli in pericardial fluid or on a histological section of the pericardium; "probable" tuberculous pericarditis is based on the proof of tuberculosis elsewhere in a patient with otherwise unexplained pericarditis, a lymphocytic pericardial exudate with elevated adenosine deaminase levels, and/or appropriate response to a trial of antituberculosis chemotherapy. Treatment consists of the standard 4-drug antituberculosis regimen for 6 months. It is uncertain whether adjunctive corticosteroids are effective in reducing mortality or progression to constriction. Surgical resection of the pericardium remains the appropriate treatment for constrictive pericarditis. The timing of surgical intervention is controversial, but many experts recommend a trial of medical therapy for noncalcific pericardial constriction, and pericardiectomy in nonresponders after 4 to 8 weeks of antituberculosis chemotherapy. CONCLUSIONS: Research is needed to improve the diagnosis, assess the effectiveness of adjunctive steroids, and determine the impact of HIV infection on the outcome of tuberculous pericarditis.

Africa↗
PubMed2005

Genotype at the -174G/C polymorphism of the interleukin-6 gene is associated with common carotid artery intimal-medial thickness: family study and meta-analysis.

BACKGROUND AND PURPOSE: Studies in unrelated individuals have produced conflicting findings concerning the putative association between the interleukin-6 (IL-6) -174G/C polymorphism and carotid intimal-medial thickness (IMT). We have used a family-based genetic association design to assess the heritability of carotid IMT and to investigate the hypothesized association of carotid IMT with the IL-6 to -174G/C polymorphism. METHODS: We studied 854 members of 224 white British families. The heritability of carotid IMT was determined using Multipoint Engine for Rapid Likelihood Inference. Genetic association analyses were carried out using ANOVA and family-based tests of association implemented in Quantitative Transmission Disequilibrium Test. A meta-analysis of previous studies of the association was conducted to place our result in context. RESULTS: The heritability of carotid IMT was 24%. Under a recessive model (GG+GC versus CC), there was significant evidence of association between IL-6 to the -174G/C genotype and adjusted log(e) maximal carotid IMT (F=5.469; P=0.02). Family-based analyses using Quantitative Transmission Disequilibrium Test showed no evidence of population stratification as a cause of the observed association (chi2(1)=0.469; P=0.4934). The CC genotype was associated with a 4.8% increase in maximal carotid IMT and accounted for 0.6% of the observed variation in the trait, which is equivalent to 2.5% of the heritable component. A meta-analysis of the present and 2 previous large studies, which enrolled a total of 2930 subjects, confirmed the recessive effect of the C allele on carotid IMT (P=0.0014). CONCLUSIONS: The genotype at the IL-6 to -174G/C polymorphism is associated with common carotid artery IMT, although the size of the genetic effect is small.

Adult↗
PubMed2005

Antibiotics for the primary prevention of acute rheumatic fever: a meta-analysis.

BACKGROUND: Rheumatic fever continues to put a significant burden on the health of low socio-economic populations in low and middle-income countries despite the near disappearance of the disease in the developed world over the past century. Antibiotics have long been thought of as an effective method for preventing the onset of acute rheumatic fever following a Group-A streptococcal (GAS) throat infection; however, their use has not been widely adopted in developing countries for the treatment of sore throats. We have used the tools of systematic review and meta-analysis to quantify the effectiveness of antibiotic treatment for sore throat, with symptoms suggestive of group A streptococcal (GAS) infection, for the primary prevention of acute rheumatic fever. METHODS: Trials were identified through a systematic search of titles and abstracts found in the Cochrane Central Register of Controlled Trials (Cochrane Library Issue 4, 2003), MEDLINE (1966-2003), EMBASE (1966-2003), and the reference lists of identified studies. The selection criteria included randomised or quasi-randomised controlled trials comparing the effectiveness of antibiotics versus no antibiotics for the prevention of rheumatic fever in patients presenting with a sore throat, with or without confirmation of GAS infection, and no history of rheumatic fever. RESULTS: Ten trials (n = 7665) were eligible for inclusion in this review. The methodological quality of the studies, in general, was poor. All of the included trials were conducted during the period of 1950 and 1961 and in 8 of the 10 trials the study population consisted of young adult males living on United States military bases. Fixed effects, meta-analysis revealed an overall protective effect for the use of antibiotics against acute rheumatic fever of 70% (RR = 0.32; 95% CI = 0.21-0.48). The absolute risk reduction was 1.67% with an NNT of 53. When meta-analysis was restricted to include only trials evaluating penicillin, a protective effect of 80% was found (Fixed effect RR = 0.20, 95% CI = 0.11-0.36) with an NNT of 60. The marginal cost of preventing one case of rheumatic fever by a single intramuscular injection of penicillin is approximately USD 46 in South Africa. CONCLUSION: Antibiotics appear to be effective in reducing the incidence of acute rheumatic fever following an episode of suspected GAS pharyngitis. This effect may be achieved at relatively low cost if a single intramuscular penicillin injection is administered.

Acute Disease↗
PubMed2005

Association between common polymorphisms of the proopiomelanocortin gene and body fat distribution: a family study.

Rare mutations in the proopiomelanocortin (POMC) gene cause severe early-onset childhood obesity. However, it is unknown whether common variants in POMC are responsible for variation in body weight or fat distribution within the commonly observed range in the population. We tested for association between three polymorphisms spanning the POMC gene and obesity phenotypes in 1,428 members of 248 families. There was significant association between genotypes at the C8246T (P < 0.0001) and C1032G (P = 0.003) polymorphisms and waist-to-hip ratio (WHR) corrected for age, sex, smoking, exercise, and alcohol consumption. Each T allele at C8246T (or G allele at C1032G) was associated with a 0.2-SD-higher WHR in a codominant fashion. When WHR was additionally corrected for BMI, thus providing a measure of body fat distribution throughout the range of BMI, there remained significant evidence for association with both markers that was of similar magnitude and statistical significance. There was no association between genotype at any polymorphism and BMI or plasma leptin level. These data show that genetic variants at the POMC locus influence body fat distribution within the normal range, suggesting a novel role for POMC in metabolic regulation.

Adipose Tissue↗
PubMed2005

Lack of adherence to the national guidelines on the prevention of rheumatic fever.

OBJECTIVES: To explore the extent to which current practices for the secondary prevention of rheumatic fever (RF) in Cape Town adhere to those outlined in the national guidelines on the primary prevention and prophylaxis of RF and rheumatic heart disease (RHD) for health professionals at primary level. METHODS: A combination of qualitative tools was used to evaluate the four priority issues identified in the guidelines as fundamental elements of a comprehensive programme for the secondary prophylaxis of RF/RHD: (i) health education and promotion; (ii) case detection of RF and RHD; (iii) secondary prophylaxis every 3-4 weeks at primary level; and (iv) notification of acute rheumatic fever (ARF). The qualitative tools included parent/child interviews of cases diagnosed with ARF in the Cape metropole area during the period 1999-2003; a physician questionnaire focused on awareness and adherence to the national guidelines; and a review of the records on acute rheumatic fever notification in the Cape metropole area from 1999 to 2003. RESULTS: The evaluation revealed four key findings. First, patient knowledge on the disease was almost non-existent. Despite this lack of knowledge, adherence to secondary prophylactic treatment was good. Second, the physicians most likely to encounter a case of rheumatic fever were least likely to be aware of and to comply with the national guideline. Third, the guidelines do not clearly state how increased detection of ARF will be achieved. Finally, the RF notification system is dysfunctional, with discrepancies in the reporting of cases at hospital, city and provincial levels. CONCLUSIONS: Since the publication of the national guidelines in 1997, little progress has been made towards achieving the implementation of a comprehensive programme for the secondary prevention of RF/RHD.

Disease Notification↗
PubMed2005

Pentoxifylline for heart failure: a systematic review.

BACKGROUND: Recent trials have indicated a beneficial effect of pentoxifylline on measures of inflammation and markers of cardiac dysfunction in people with heart failure. However, it is uncertain whether pentoxifylline should be used routinely in the management of heart failure. OBJECTIVE: To determine the effectiveness of pentoxifylline in heart failure. DESIGN: Systematic review of randomised controlled trials. METHODS: We searched MEDLINE (1 January 1966 - 20 November 2004), the Cochrane Controlled Trials Register (issue 4, 2004), and reference lists of related papers, for randomised controlled trials of pentoxifylline in the treatment of heart failure. Prospective, randomised, double-blind controlled trials were sought for inclusion in the study. The two reviewers independently assessed trial quality and extracted data, which were analysed using RevMan statistical software. The following outcome measures were evaluated: (i) New York Heart Association (NYHA) functional class; (ii) left ventricular ejection fraction (LVEF); (iii) frequency of hospitalisation; and (iv) death from all causes. RESULTS: Four studies with a total of 144 participants met the inclusion criteria. Statistical pooling (or meta-analysis) was not performed owing to the significant clinical heterogeneity and differences in reporting of the outcomes in the included studies; instead, the trials were analysed separately for the outcomes of interest. The four studies tested the use of pentoxifylline versus placebo in patients with heart failure of varying aetiology (idiopathic dilated cardiomyopathy, 3 studies; ischaemic cardiomyopathy, 1 study). In 2 of the idiopathic dilated cardiomyopathy studies, patients were classified as NYHA class II or III, while the study population in another idiopathic cardiomyopathy study was in NYHA class IV. The trial of patients with ischaemic cardiomyopathy included patients in NYHA functional classes I - IV. The use of pentoxifylline was associated with significant improvement in symptoms (i.e. NYHA functional class) and cardiac function (i.e. LVEF) in 3 out of 4 studies. The beneficial effect on symptoms of heart failure and cardiac function was seen in all grades of severity of heart failure and in patients with ischaemic and idiopathic dilated cardiomyopathy. All 4 studies showed a trend towards reduction of mortality, but this effect was not statistically significant. The effect of pentoxifylline on the frequency of hospitalisation has not been tested in randomised controlled trials. INTERPRETATION: Pentoxifylline may have a beneficial effect on NYHA functional class, ejection fraction and mortality in heart failure, but published trials are too small to provide conclusive evidence. There is a need for large, placebo-controlled trials of pentoxifylline in heart failure, involving a diverse group of patients with regard to cause and severity of heart failure.

Double-Blind Method↗
PubMed2003

Measured haplotype analysis of the aldosterone synthase gene and heart size.

Gene-association studies of heart size and the aldosterone synthase (CYP11B2) gene have produced inconsistent results, possibly because of limitations in the sample size and/or the number and location of the polymorphisms. An analysis of six polymorphisms spanning 6 kb of the CYP11B2 gene in Caucasian British families revealed a limited number of haplotypes because of strong linkage disequilibrium over this small region. The genotype and haplotype information was used in an association study involving 955 members of 229 families phenotyped for echocardiographic measures of heart size. In a mixed effects linear modelling analysis, the G5937C polymorphism was associated with cardiac wall thickness (P=0.02), and the intron conversion and A4550C polymorphisms were associated with left ventricular cavity size (P=0.02 and 0.002, respectively). Measured haplotype analyses confirmed the association of alleles at the intron conversion and G5937C polymorphisms with cardiac wall thickness (P=0.02), and alleles at the intron conversion polymorphism with left ventricular cavity size (P=0.04). The polymorphisms contributed to 2.0-3.4% of the variability in these traits. In summary, genetic polymorphisms at the CYP11B2 gene make a small contribution to quantitative variation in echocardiographic measures of heart size. These results point to the importance of analysing the full extent of genetic variation that captures the haplotype structure of a locus in gene association studies.

Cytochrome P-450 CYP11B2↗
PubMed2003

Intramuscular penicillin is more effective than oral penicillin in secondary prevention of rheumatic fever--a systematic review.

BACKGROUND: People with a history of rheumatic fever (RF) are at high risk of recurrent attacks and of developing rheumatic heart disease following a streptococcal throat infection. Giving penicillin to these people can prevent recurrent attacks of RF and subsequent rheumatic heart disease. However, there is no agreement on the most effective method of giving penicillin. OBJECTIVES: To assess the effects of different penicillin regimens and formulations for preventing streptococcal infection and RF recurrence. SEARCH STRATEGY: We searched the Controlled Trials Register (Cochrane Library Issue 2, 2001), Medline (January 1966-July 2000), Embase (January 1985-July 2000), reference lists of articles, and contacted experts in the field. SELECTION CRITERIA: Randomised and quasi-randomised studies comparing: (i) oral with intramuscular penicillin; and (ii) 2- or 3-weekly with 4-weekly intramuscular penicillin in patients with previous RF. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS: Six studies were included (1,707 patients). Data were not pooled because of clinical and methodological heterogeneity of the trials. Four trials (1,098 patients) compared intramuscular with oral penicillin and all showed that intramuscular penicillin was more effective in reducing RF recurrence and streptococcal throat infections than oral penicillin. One trial (360 patients) compared 2-weekly with 4-weekly intramuscular penicillin. Penicillin given every 2 weeks was better at reducing RF recurrence (relative risk (RR) 0.52, 95% confidence interval (CI): 0.33-0.83) and streptococcal throat infections (RR 0.60, 95% CI: 0.42-0.85). One trial (249 patients) showed that 3-weekly intramuscular penicillin injections reduced streptococcal throat infections (RR 0.67, 95% CI: 0.48-0.92) compared with 4-weekly intramuscular penicillin. CONCLUSIONS: Intramuscular penicillin seemed to be more effective than oral penicillin in preventing RF recurrence and streptococcal throat infections. Two-weekly or 3-weekly injections appeared to be more effective than 4-weekly injections. However, the evidence is based on poor-quality trials and the use of outdated formulations of oral penicillin.

Administration, Oral↗
PubMed2002

Genotype at a promoter polymorphism of the interleukin-6 gene is associated with baseline levels of plasma C-reactive protein.

OBJECTIVE: Baseline concentrations of plasma C-reactive protein (CRP) are associated with coronary heart disease. Interleukin-6 (IL-6) regulates CRP gene expression; a promoter polymorphism (-174G/C) of the IL-6 gene has been shown to influence IL-6 transcription but the relationship between genotype at this polymorphism and circulating levels of inflammatory markers remains unclear. We hypothesised that plasma CRP would be a heritable phenotype that would be influenced by genotype at this polymorphism. METHODS: We measured baseline plasma CRP and determined genotypes at the -174G/C polymorphism of the IL-6 gene in 588 members of 98 nuclear families. The heritability of plasma CRP and the association of plasma CRP with genotype were determined using variance components methods. RESULTS: Baseline CRP levels were highly heritable (h(2)=0.39, P<0.0000001). Presence of the -174C allele was associated with higher baseline CRP levels, both in the whole population (P=0.01), and in the founders only (n=128, P=0.001). Family-based analyses confirmed the association (P=0.02) suggesting that it arises from chromosomal proximity or identity of the typed polymorphism with a genetic variant influencing baseline CRP levels. CONCLUSIONS: Baseline plasma CRP is a significantly heritable cardiovascular risk factor. Levels are associated with genotype at the -174G/C polymorphism of the IL-6 gene.

Adult↗