Concordance of two multiple analytical approaches demonstrate that interaction between BMI and ADIPOQ haplotypes is a determinant of LDL cholesterol in a general French population.

Genetic and environmental factors are involved in insulin resistance (IR). IR and dyslipidemia associate with increased risk of cardiovascular diseases. Plasma low-density lipoprotein cholesterol (LDL-C) level is a marker of cardiovascular risk. In a Caucasian general population we aimed at determining the multifactorial components of LDL-C levels using 10 genes and 3 phenotypes. In the PPARG, UCP3, ADIPOQ, TNF, LIPC, CARTPT, PCSK9, SCAP, SCARB1 and ENPP1 genes known to be associated with IR or dyslipidemia we genotyped 19 single nucleotide polymorphisms (SNPs) in 846 subjects. When several SNPs were genotyped for a given gene we constructed haplotypes. Including genetic and environmental variables (gender, body mass index (BMI) and adiponectin level) we used (1) the multifactor dimensionality reduction method to explain clusters of high and low LDL-C, and (2) the restricted partition method to explain LDL-C levels. Both methods showed that BMI and haplotypes at the ADIPOQ adiponectin encoding gene but not adiponectin level itself, were discriminant regarding to LDL-C. Subjects bearing an at-risk combination of BMI and ADIPOQ genotypes were prone to have a higher LDL-C (OR=3.13, 95% CI=2.20-4.46, P<0.0001). Our results suggest that in interaction with BMI, ADIPOQ haplotypes capture genetic variation(s) from neighboring gene(s) that would modulate LDL-C level.

Angiotensin I-converting enzyme I/D polymorphism and suicidal behaviors.

Suicide is one of the ten most common causes of death in Western countries. It involves genetic vulnerability factors and is often associated with major depression. A Japanese team reported an association between the insertion allele of the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with completed suicide. The ACE I/D polymorphism was investigated in two independent case-control studies, one involving 64 suicide completers and 90 controls who all underwent forensic investigations, the second one consisting of 588 suicide attempters and 639 controls. In the two population samples studied a statistically significant risk of suicidal behavior was observed for subjects bearing the DD genotype. These results suggest a possible role of the renin-angiotensin system in suicidal behavior.

Haplotypes across ACE and the risk of Alzheimer's disease: the three-city study.

The purpose of this study was to examine the impact of two polymorphisms (rs4291A>T and rs4343G>A) in the ACE gene on the risk of Alzheimer's disease (AD), using a population-based cohort of 9294 subjects selected from the electoral rolls of three French cities (the Three-City Study). Two follow-up examinations took place 2 and 4 years after inclusion. Diagnosis of dementia was assessed at baseline and at each follow-up examination by neurologists independent of the 3C Study group. For the present analysis, subjects whose mother tongue was not French, those from abroad and those lost at follow-up were excluded, leaving a sample of 6791 subjects. 108 subjects were demented at baseline and 216 subjects, among which 141 had AD, developed a dementia during follow-up. The genotype distributions of the ACE SNPs rs4291 and rs4343 did not differ according to cognitive status. After adjustment for confounding variables, the risk of developing AD was similar whatever the genotype (rs4291 AT vs TT: OR=0.90, p=0.65; AA vs TT: OR=1.05, p= 0.84; rs4343 GA vs GG: OR=1.15, p= 0.48; AA vs GG: OR=1.25, p= 0.37). No global haplotype effect could be observed on the risk of AD.

An apolipoprotein A-I gene promoter polymorphism associated with cognitive decline, but not with Alzheimer's disease.

BACKGROUND/AIMS: Accumulating biological and epidemiological evidence suggests a close link between cholesterol metabolism and the pathophysiology of Alzheimer's disease (AD). The observation that the use of statins reduces the risk of AD sustains this hypothesis. Apolipoprotein A-I (APOA1) is the major component of the high-density lipoproteins, particles involved in reverse cholesterol transport. Therefore, genetic polymorphisms in the gene encoding APOA1 might influence cholesterol metabolism and be a risk factor for AD. A previous study suggested an impact of a G-->A polymorphism at position -75 bp in the APOA1 gene on the risk for early-onset AD and on the age at onset of the disease. We studied this polymorphism in 3 independent European population samples. METHODS: Genotyping was conducted asdescribed in the previous study. RESULTS: We were unable to show any impact of this polymorphism on the risk of AD. Conversely, subjects bearing the A allele of this polymorphism were at risk of cognitive decline. CONCLUSION: Our resultssuggest an impact of the G-->A polymorphism at position -75 bp in the APOA1 gene on cognitive impairment, but not on the risk of AD.

A prospective evaluation of left ventricular remodeling after inaugural anterior myocardial infarction as a function of gene polymorphisms in the renin-angiotensin-aldosterone, adrenergic, and metalloproteinase systems.

BACKGROUND: Left ventricular remodeling (LVR) is a strong predictor of cardiovascular events after myocardial infarction (MI). Although several factors have been shown to influence LVR, interindividual variability exists. Some studies have suggested that gene polymorphisms may be associated with LVR, but these studies were limited by either a retrospective design or the inclusion of limited patient numbers. The present study was designed to prospectively assess the impact of gene polymorphisms on LVR. METHODS: We included 266 patients with inaugural anterior MI. Systematic echocardiographic follow-ups were performed at 3 months and at 1 year after MI. The polymorphisms were selected using a candidate gene approach based on LVR pathophysiology. We analyzed 14 polymorphisms in 3 different systems: the renin-angiotensin-aldosterone system (ACE I/D, RAT1 1166A/C, angiotensinogen M235T, CYP11B2 -344C/T), the adrenergic system (beta1AR Ser49Gly, beta1AR Gly389Arg, beta2AR Gly16Arg, beta2AR Gln27Glu, beta2AR Thr164Ile, alpha2cAR Del322-325), and the metalloproteinase (MMP) system (-1607 1G/2G MMP-1, -1306 C/T MMP-2, -1171 5A/6A MMP-3, -1562 C/T MMP-9). RESULTS: Left ventricular remodeling was documented by a progressive increase in end-diastolic volume from 56.5 +/- 14.9 mL/m2 at baseline to 62.8 +/- 18.8 mL/m2 at 1 year (P < .0001). End-diastolic volume at baseline, 3 months, or 1 year did not differ significantly among genotypes for any polymorphism. The change in end-diastolic volume from baseline to 1 year was also similar among genotypes for all polymorphisms. CONCLUSIONS: Left ventricular remodeling after MI is not associated with common polymorphisms in the renin-angiotensin-aldosterone, adrenergic, or MMP systems.

The impact of the AMPD1 gene polymorphism on exercise capacity, other prognostic parameters, and survival in patients with stable congestive heart failure: a study in 686 consecutive patients.

BACKGROUND: Previous studies have demonstrated that the adenosine monophosphate deaminase 1 (AMPD1) C34T polymorphism may be associated with survival in cardiac populations with a protective effect of the T allele. However, these studies included limited number of patients with few cardiovascular events. METHODS: We prospectively analyzed the impact of the C34T polymorphism of the AMPD1 gene in 686 unrelated white patients with stable congestive heart failure related to left ventricular systolic dysfunction. Patients underwent echocardiography, radionuclide angiography, and a cardiopulmonary exercise test. Blood samples were drawn for standard and hormonal determinations and for genetic analysis. RESULTS: There were 517 (75%) CC homozygotes, 155 (23%) CT heterozygotes, and 14 (2%) TT mutated homozygotes. We did not demonstrate any impact of this polymorphism on clinical, biologic, echocardiographic, radionuclide, and exercise parameters in the whole population and in ischemic and nonischemic subgroups of patients. During a median follow-up period of 3 years, there were 145 cardiac-related deaths and 6 urgent transplantations. There was no impact of this polymorphism on survival. CONCLUSIONS: In our population, we did not demonstrate any effect of the C34T polymorphism of the AMPD1 gene on major congestive heart failure parameters and on survival.

The serotonin transporter promoter polymorphism and suicide.

Serotonergic dysfunction has been implicated in mood disorders and in the pathophysiology of suicidality. A functional polymorphism (a 44-base pair insertion (L)/deletion (S)) in the promoter of the gene encoding the serotonin transporter (5-HTTLPR), associated with mood disorders, has been inconsistently associated with suicidality. To add to this debate, we designed a case-control study involving 62 suicide victims and 72 controls matched for age, gender and ethnicity. All subjects underwent forensic investigation. No association could be detected between the 5-HTTLPR polymorphism and suicide. This result is consistent with the proposal that different genes are involved in hopelessness and suicidal behavior or in depressive illness.

Impact of APOA5/A4/C3 genetic polymorphisms on lipid variables and cardiovascular disease risk in French men.

OBJECTIVE: The goal of the present study was to assess the impact of 4 single nucleotide polymorphisms (SNPs) of APOA5/A4/C3 gene cluster on lipid levels and coronary heart disease (CHD) risk in French men. METHODS: A total of 442 men with CHD were recruited from the university hospital and compared to 475 men free of CHD from the population of the same geographical area. The APOA5 S19W, APOA5 -l2,238T>C, APOA4 T347S and APOC3 -482C>T SNPs were examined. RESULTS: The APOA5 S19W polymorphism was associated with plasma triglyceride levels. In multivariate logistic regression analyses the odds ratio (OR [95% Cl]) of hypertriglyceridemia (3rd vs. 1st tertile of triglyceride distribution) was 3.60 [1.38-9.42] in control subjects bearing at least one APOA5 19W variant. Haplotype analyses revealed a significant association between the 2111 haplotype and high triglyceride levels (+1.94 +/- 0.63 vs. 0.74 +/- 0.36 mmol/l for the 1111 haplotype p < 0.002). There was, in contrast, no significant difference in SNP distribution between CHD patients and controls. The age-adjusted OR of CHD were 1.46 [0.96-2.23], 0.79 [0.60-1.05], 0.91 [0.69-1.21] and 0.91 [0.69-l.22] in carriers of the APOA5 19W, APOA5 -12,238C, APOA4 347S and APOC3 -482T variants, respectively. There was also no significant difference in APOA5/A4/C3 haplotype distribution in patients and controls. CONCLUSION: The APOA5 19W variant is associated with increased plasma triglycerides. However, there is no evidence that APOA5 S19W, -12,238T > C, APOA4 T347S and APCC3 -482C > T SNPs are major risk factors of CHD in French men.

Polymorphisms in the promoter regions of MMP-2, MMP-3, MMP-9 and MMP-12 genes as determinants of aneurysmal coronary artery disease.

OBJECTIVES: Our hypothesis was that functional polymorphisms in matrix metalloproteinase (MMP) genes may act as susceptibility factors for the development of coronary aneurysms (CAs). BACKGROUND: Different forms of remodeling have been described at the level of coronary arteries; CA, reported in 1% to 5% of patients with angiographic evidence of coronary artery disease (CAD), are one of them. Matrix metalloproteinases have been implicated in the pathogenesis of aneurysm development through increased proteolysis of extracellular matrix proteins. METHODS: We screened 3,862 patients who underwent coronary angiography and identified 113 patients with CAD with at least one CA (CA group); these patients were matched with 226 patients with CAD without CA (control group). The -1,306 C/T MMP-2, 5A/6A MMP-3, CA-repeat MMP-9 and -82 A/G MMP-12 polymorphisms were determined. RESULTS: The MMP-2, MMP-9 and MMP-12 polymorphisms were not associated with CA. By contrast, the 5A/5A genotype of MMP-3 was significantly more frequent in the CA group than in the control group (31% vs. 18%, p = 0.015); similarly, the MMP-3 5A allele was more frequent in the CA group (p = 0.009). Three variables were independently associated with CA: the MMP-3 5A/5A genotype (odds ratio [OR] = 2.23, 95% confidence interval [CI] [1.27 to 3.93]), a previous myocardial infarction (OR = 1.91, 95% CI [1.14 to 3.20]) and a history of aortic aneurysm (OR = 21.06, 95% CI [2.35 to 188]). CONCLUSIONS: The MMP-3 5A allele is associated with the occurrence of CA. Our results suggest that an increased proteolysis in the arterial wall may act as a susceptibility factor for the development of CA in patients with coronary atherosclerosis.

The impact of beta-adrenoreceptor gene polymorphisms on survival in patients with congestive heart failure.

OBJECTIVE: Discordant results have been published regarding a possible association between beta-adrenoreceptor (betaAR) gene polymorphisms and survival in patients with congestive heart failure (CHF). The aim of the study was to analyze the impact of five functional betaAR gene polymorphisms in patients with stable CHF. METHODS: We prospectively studied 444 consecutive patients with CHF related to left ventricular systolic dysfunction. The beta1ARSer49Gly, beta1ARGly389Arg, beta2AR Arg16Gly, beta2AR Gln27Glu and beta2AR Thr164Ile polymorphisms were determined. Patients underwent echocardiography, radionuclide angiography and a cardiopulmonary exercise test. RESULTS: Mean age was 56.6+/-11.9 years old, left ventricular ejection fraction (LVEF) was 32+/-12%, and peak VO2 was 15.5+/-4.9 ml/min/kg or 63+/-18% of maximal predicted VO2. Most of the patients (95%) were receiving angiotensin converting enzyme inhibitors and 91% beta-blockers. There was no statistically significant differences between baseline characteristics among beta1AR and beta2AR genotypes. During a median follow-up period of 1232 days, there were 110 cardiac-related deaths and five urgent transplantations. Independent predictors of survival were percent (%) of maximal predicted VO2 (p<0.0001), age (p<0.0001), LVEF (p=0.004), creatinine (p=0.02) and atrial fibrillation (p=0.04). No betaAR polymorphisms were associated with survival. However, patients with the combined beta2ARGly16Gly/beta2ARGln27Gln genotype, who express receptors highly sensitive to down-regulation, had a significantly lower survival rate than patients with other genotypes but only in univariate analysis. CONCLUSIONS: In this prospective study, we found no association between five functional betaAR polymorphisms and survival in patients with stable CHF. However, we demonstrated, only in univariate analysis, a possible association between the combined beta2ARGly16Gly/beta2ARGln27Gln genotype and survival.

Analysis of sequence variability in the CART gene in relation to obesity in a Caucasian population.

BACKGROUND: Cocaine and amphetamine regulated transcript (CART) is an anorectic neuropeptide located principally in hypothalamus. CART has been shown to be involved in control of feeding behavior, but a direct relationship with obesity has not been established. The aim of this study was to evaluate the effect of polymorphisms within the CART gene with regards to a possible association with obesity in a Caucasian population. RESULTS: Screening of the entire gene as well as a 3.7 kb region of 5' upstream sequence revealed 31 SNPs and 3 rare variants; 14 of which were subsequently genotyped in 292 French morbidly obese subjects and 368 controls. Haplotype analysis suggested an association with obesity which was found to be mainly due to SNP-3608T>C (rs7379701) (p = 0.009). Genotyping additional cases and controls also of European Caucasian origin supported further this possible association between the CART SNP -3608T>C T allele and obesity (global p-value = 0.0005). Functional studies also suggested that the SNP -3608T>C could modulate nuclear protein binding. CONCLUSION: CART SNP -3608T>C may possibly contribute to the genetic risk for obesity in the Caucasian population. However confirmation of the importance of the role of the CART gene in energy homeostasis and obesity will require investigation and replication in further populations.

A functional polymorphism in a STAT5B site of the human PPAR gamma 3 gene promoter affects height and lipid metabolism in a French population.

OBJECTIVE: The peroxisome proliferator-activated receptor-gamma (PPARgamma) plays a role in adipocyte differentiation and insulin sensitization. It has been shown that genetic variation in the PPARgamma gene alters body weight control, lipid and insulin homeostasis, and the susceptibility to type 2 diabetes. Four PPARgamma isoforms are generated by alternative splicing and promoter usage. PPARgamma3 is only expressed in adipose tissue, colon, and macrophages and therefore seems to be a good candidate gene for metabolic and cardiovascular-associated diseases. In the present study, we looked for genetic variation in the PPARgamma3 promoter. METHODS AND RESULTS: The proximal PPARgamma3 promoter was sequenced in 20 individuals. We detected a C/G polymorphism at position -681 from exon A2. Interestingly, it was located in a signal transducer and activator of transcription 5B (STAT5B) binding consensus site. In a French population (n=836), the -681G allele was associated with increased height and plasma low-density lipoprotein cholesterol concentrations. In vitro, we showed that the -681G allele completely abolished the binding of STAT5B to the cognate promoter element as well as the transactivation of the PPARgamma3 promoter by the growth hormone/STAT5B pathway. CONCLUSIONS: Our results suggest that PPARgamma3 may regulate the control of height and lipid homeostasis via the STAT5B pathway.

A common variant of endothelial nitric oxide synthase (Glu298Asp) is associated with collateral development in patients with chronic coronary occlusions.

BACKGROUND: Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions. METHODS: We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques. RESULTS: Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 +/- 0.08 and 2.89 +/- 0.08, respectively, p = 0.04; recipient filling grade: 3.00 +/- 0.08 and 3.24 +/- 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03). CONCLUSION: Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development.

The Gly16-->Arg16 and Gln27-->Glu27 polymorphisms of beta2-adrenergic receptor are associated with metabolic syndrome in men.

Endogenous catecholamines contribute to regulation of adipose tissue lipolysis, glucose homeostasis, and vascular tone. The goal of the present study was to assess the association between the Gly(16)-->Arg(16) and Gln(27)-->Glu(27) polymorphisms of the beta(2)-adrenergic receptor and metabolic syndrome. Participants were recruited in a population survey and included 1195 men and women. Metabolic syndrome was defined according to National Cholesterol Education Program Adult Treatment Panel III guidelines. There were 276 patients with metabolic syndrome and 872 controls. The Gly(16)-->Arg(16) (P < 0.005) and Gln(27)-->Glu(27) (P < 0.04) polymorphisms were associated with metabolic syndrome in men, but not in women. In multivariate analyses adjusting for age, physical activity, smoking habits, alcohol consumption, and body mass index, the odds ratio of metabolic syndrome was 1.83 (95% confidence interval, 1.10-3.05) and 2.43 (95% confidence interval, 1.19-4.95) in men bearing the Gly(16)/Arg(16) and Arg(16)/Arg(16) genotypes, respectively. Similarly, the odds ratios of metabolic syndrome were 0.99 (95% confidence interval, 0.50-1.93) and 1.67 (95% confidence interval, 0.84-3.33) in men bearing the Gln(27)/Glu(27) and Gln(27)/Gln(27) genotypes, respectively. Because both variants were in linkage disequilibrium, a haplotype analysis was performed. There was no evidence of any statistically significant association between beta(2)-adrenergic receptor haplotypes and metabolic syndrome. In conclusion, these data suggest that the Arg(16) and Gln(27) variants of the beta(2)-adrenergic receptor gene contribute to metabolic syndrome susceptibility in men.

Significant impact of the highly informative (CA)n repeat polymorphism of the APOA-II gene on the plasma APOA-II concentrations and HDL subfractions: The ECTIM study.

High density lipoproteins (HDL) are heterogeneous in their apolipoprotein composition and the role of apolipoprotein A-II (APOA-II) in HDL structure and metabolism is poorly understood. Yet, studies of naturally occurring variations of APOA-II in mice and experiments in transgenic mice overexpressing the APOA-II gene (APOA-II) have shown that APOA-II expression influences APOA-II plasma levels and HDL size and composition. In humans, two RFLPs (BstNI and MspI) have been described in the APOA-II gene. These RFLPs, however, have been inconstantly associated with variations in APOA-II plasma levels. In particular, the large multicentric ECTIM Study did not show any significant effect of the two RFLPs. Other polymorphisms consisting of repetitive sequences have been proposed as more informative markers than RFLPs. Thus, data from the ECTIM Study were reconsidered by integrating the additional information obtained from a highly informative multiallelic (CA)(n)-repeat polymorphism located in the second intron of the gene. The population study was composed of 763 non-treated male controls and 594 cases of myocardial infarction. In controls, the (CA)(19) allele was associated with significantly decreased APOA-II (P < 0.0009) and LpA-II:A-I (P < 0.02) plasma levels. Although the APOA-I plasma levels were not affected by the polymorphism, the (CA)(19) allele was associated with an increased LpA-I/LpA-II:A-I ratio (P < 0.004). No effect, however, could be detected on myocardial infarction. Study of the linkage disequilibrium and the estimation of haplotype frequencies indicated that the impact of the APOA-II locus could hardly be detected by using the BstNI and MspI RFLPs. These data revive interest in evaluating the role of the APOA-II locus in the control of APOA-II plasma levels and HDL composition.

Beta-adrenergic receptor blockade and the angiotensin-converting enzyme deletion polymorphism in patients with chronic heart failure.

BACKGROUND: Beta-adrenergic receptor blockade is an established treatment of chronic heart failure (HF). Previous studies have suggested a potential pharmacogenetic interaction between beta-blocker therapy and the angiotensin-converting enzyme (ACE) I/D polymorphism in patients with HF. AIMS: We designed this study to analyze changes in myocardial function of HF patients in response to beta-blocker therapy as a function of the ACE I/D polymorphism. METHODS AND RESULTS: We studied 199 consecutive patients with chronic HF not treated with beta-blockers. Before initiation of beta-blockers and 3 months after the maximal tolerated dose was reached, patients underwent echocardiography, radionuclide angiography, and a cardiopulmonary exercise test. We extracted genomic DNA from white blood cells and determined the ACE I/D polymorphism. Thirty-five (18%) patients had the II genotype, 86 (43%) the ID genotype and 78 (39%) the DD genotype. A significant and similar improvement in left ventricular ejection fraction (LVEF) was observed in II (from 0.30+/-0.10 to 0.41+/-0.13; P<0.0001), ID (from 0.29+/-0.11 to 0.39+/-0.13; P<0.0001) and DD patients (from 0.31+/-0.11 to 0.40+/-0.13; P<0.0001). Peak Vo(2) before and after beta-blockade was similar among the three groups. The proportion of responders to beta-blockers (patients without cardiac events during titration who had an increase in LVEF >5% after beta-blockers) was similar among the three groups (II: 65.9%%, ID: 60.6%%, DD: 65.9%; P=NS). During a median follow-up of 933 days, there was no evidence for any effect of ACE I/D polymorphism on cardiac survival. CONCLUSIONS: We observed no evidence of pharmacogenetic interaction between the ACE I/D polymorphism and the effects of beta-blockade on LVEF and other prognostic parameters in patients with chronic HF. Our results support the initiation of beta-blockers in HF patients with the II or the ID genotype as well as in those with the DD genotype.

The role of matrix metalloproteinase-9 in dementia.

Neurofibrillary tangles and senile plaques, constituted of extracellular amyloid deposits (Abeta), are the two defining pathological hallmarks of Alzheimer's disease (AD). Inhibiting the synthesis or aggregation of Abeta or increasing its clearance may reduce the detrimental effects of this peptide and consequently improve cognitive functions in patients. Previous studies indicated that metalloproteinases are involved in Abeta degradation and the presence of matrix metalloproteinases (MMP) in AD plaques has been described. In this study, we examined the distribution of a functional polymorphism in the gene for MMP-9, -1562 C-->T, in an independent population of 229 demented and 253 control individuals. We observed a weak protective effect of the high activity allele (T) in apolipoprotein E epsilon4 allele non-bearers (odds ratio=0.5 (95% confidence interval, 0.3-0.9), P=0.04).

Paraoxonase 1 gene polymorphisms and dementia in humans.

Several clinical and epidemiological studies suggest that Alzheimer's disease (AD) and vascular dementia share common risk factors. Oxidative stress is one of these well recognized factors. It can result from an excess of free-radical activity and impaired antioxidant defenses. Paraoxonase (PON1), a component of high density lipoproteins, has antioxidative potential and was previously associated with an increased risk of cardiovascular diseases. The impact of two polymorphisms in PON1 (Gln192Arg associated with enzyme activity and T-107C associated with enzyme concentration) was examined in a case-control study. The two polymorphisms were independent risk factors for nonAD dementia, particularly in APOE-4 noncarriers. An at-'risk haplotype' could be constructed including the Gln192 and the T-107 alleles, suggesting that subjects at risk have lower plasma paraoxonase levels and this enzyme is less active.

APOE promoter polymorphisms and dementia in the elderly.

Previous observations suggest a contribution of two APOE promoter polymorphisms (-219 G/T and -491 A/T) in dementia. From two independent populations of elderly (mean age of 84 and 85 years old, respectively), we observed that subjects bearing the -219T allele were at increased risk of dementia (OR = 1.9 (95% CI, 1.3-2.8), P = 0.0003) or AD (OR = 2.0 (95% CI, 1.2-3.4), P < 0.008). Conversely, the -491 A/T variant was not associated with this risk of dementia in the elderly, as previously described. Haplotype estimations including the two promoter and the coding APOE polymorphisms indicated that the -491A/-219T/4 haplotype was at risk for the development of dementia (OR = 3.5 (95% CI, 2.5-5.0), P < 0.0001), whereas the -491A/-219G/4 haplotype was not (OR = 1.1 (95% CI, 0.6-2.1)). Similar results were observed when restricted to Alzheimer's disease. In conclusion, these data indicate that the -219 G/T polymorphism is a genetic determinant of dementia in the elderly, independently of the 4 allele.

Angiotensin Converting Enzyme and Angiotensin II Type 1 Receptor Polymorphisms in Patients with Coronary Aneurysms.

BACKGROUND: Conflicting results have been reported regarding the association of gene polymorphisms in the renin-angiotensin system (RAS) with different aspects of coronary artery disease (CAD), such as myocardial infarction, neointimal hyperplasia or coronary artery vasomotion. Since previous studies have linked angiotensin II to aneurysmal disease, our study hypothesis was that RAS gene polymorphisms may be associated with aneurysm remodeling in response to CAD. METHODS: The study population was selected from a series of 3862 consecutive patients who underwent coronary angiography in our institution. One hundred and thirteen consecutive patients with at least one coronary aneurysm (CA) were compared to 226 randomized control patients without CA. DNA was extracted from white blood cells. The angiotensin-converting enzyme (ACE) I/D and angiotensin type 1 receptor (AT1-R) A/C polymorphisms were detected using previously published techniques. RESULTS: The distributions of the three ACE genotypes were similar in both groups: CA: 13%, 46%, and 41% for II, ID, and DD respectively; controls: 18%, 41%, and 41% for II, ID, and DD respectively, p = 0.45. The distributions of the three AT1-R genotypes were also similar in both groups: CA: 54%, 41%, and 5% for AA, AC, and CC respectively; controls: 55%, 33%, and 12%, for AA, AC, and CC respectively, p = 0.08. CONCLUSION: Our results provide further information on the role of RAS polymorphisms on specific mechanisms implicated in CAD. Although an activated RAS may theoretically promote aneurysm formation, the 2 RAS polymorphisms analyzed in this study are not associated with this process in coronary arteries.