The MspI restriction fragment length polymorphism 3' to the apolipoprotein A-II gene: relationships with lipids, apolipoproteins, and premature coronary artery disease.

In previous studies, a restriction fragment length polymorphism (RFLP) has been identified using MspI restriction endonuclease in the 3' region of the apo A-II gene. The rare variant site for this MspI (M2) has been reported to be associated with higher levels of HDL cholesterol and apo A-II. We have studied the frequency and lipid associations of this RFLP in a population of 168 coronary artery disease (CAD) male and female patients, who had more than 50% narrowing of one or more arteries prior to age 60 years, as well as 255 aged-matched males and females from the Framingham Offspring Study. We also studied 31 kindreds in which the proband had premature CAD. The frequency of the M2 allele was higher in CAD cases (0.20) than in the controls (0.13) (P less than 0.05). In general, those subjects carrying the M2 allele had lower HDL cholesterol and apo A-I plasma levels; however, this difference was only significant (P less than 0.02 and 0.002, respectively) in females with CAD. No cosegregation of the M2 allele with hypoalphalipoproteinemia was found in 31 kindreds studied. However, in both generations there was a trend for those subjects carrying the M2 allele to have lower HDL cholesterol levels than those carrying the M1 allele. Sequence analysis of the apo A-II gene of subjects homozygous for either the M1 (n = 1) or the M2 allele (n = 2) revealed that this RFLP is due to a T----C single base mutation 528 bp 3' to the apo A-II gene. In the subjects homozygous for the M2 allele no other mutations were found within the coding region of the apo A-II gene that could result in changes in the primary sequence of the protein. These data indicate that the MspI RFLP 3' to the apo A-II gene is somewhat more frequent in the CAD group. However, there was no significant association between this RFLP and any of the parameters examined. In conclusion, this DNA marker lacks the specificity to be clinically useful for CAD risk assessment in the population studied.     

高甘油三酯血症患者载脂蛋白B基因的MspI多态性研究

利用Apo B cDNA探针（LB 1.5）,检测13名高甘油三酯血症（HTG）患者和21名正常对照者的Apo B基因MspI限制性片段长度多态性（RFLP）等位基因频率。研究结果显示,34份标本共出现2.35kb（M_1）和2.60kb（M_2）二种不同长度的杂交片段。M_2等位基因频率在HTG患者（0.192）和对照者（0.024）之间存在明显差异（P=0.02）。     

DNA polymorphisms of the apolipoprotein B gene (XbaI, EcoRI, and MspI RFLPs) in Norwegians at risk of atherosclerosis and healthy controls.

OBJECTIVES: Apo B is the exclusive protein constituent of LDL and is ligand on LDL, recognized and bound by the LDL receptor. Several restriction fragment length polymorphisms (RFLPs) of the apo B gene have been shown to be associated with variation in serum lipid levels in different populations. In this study we sought to determine the frequency of XbaI, EcoRI, and MspI polymorphisms and the haplotypes generated by these three polymorphic sites of the apo B gene and their influence on lipid levels in a sample of Norwegian subjects at risk of atherosclerosis and healthy control subjects. METHODS AND RESULTS: 108 White Norwegians at risk of atherosclerosis (cases) and 64 healthy individuals (controls) were examined for possible association between the alleles at the XbaI (X), EcoRI (R), and MspI (M) polymorphic restriction sites of the apolipoprotein B gene and serum lipid levels. The frequency of the M allele (absence of restriction site) was significantly higher in cases with high total cholesterol (TC), high low-density lipoprotein cholesterol (LDLC), and high apolipoprotein B (apo B) than in controls with normal TC, LDLC, and apo B (P < 0.04, P < 0.02, and P < 0.01, respectively). The frequencies of apo B genotypes detected with XbaI, EcoRI, and MspI did not differ significantly between cases and control subjects. A significant association between MspI genotypes and TC (P < 0.02), LDLC (P = 0.03), and apo B (P = 0.001) was observed only in cases. However, cases with the genotype M+/M+ had the lowest and those with the genotype M+/M- had the highest levels of serum TC, LDLC, and apo B. We did not observe any significant association between the alleles or genotypes detected with XbaI or EcoRI and serum lipid levels. In cases, genotypes defined by EcoRI and MspI RFLP paired loci differed significantly for apo B (chi 2 = 19; P = 0.007) but not for other blood lipids. EcoRI and MspI RFLPs change glutamic acid (Glu) 4154 to lysine (Lys) and arginine (Arg) 3611 to glutamine (Gln), respectively, which lie near the low density lipoprotein receptor binding region of apo B. Haplotypes containing "Lys/Arg Lys/Arg" (all basic amino acids) in cases were associated with low serum TC, LDLC, and apo B. In individuals at risk of atherosclerosis the concentration of serum lipids tends to be inversely related to the number of lysine and arginine. CONCLUSION: We conclude that variations in the apo B gene, resulting in changes of charged amino acids, affect the circulating blood lipids and that these may contribute to the risk of atherosclerosis.     

Restriction fragment length polymorphisms of the apolipoprotein A-I, C-III, A-IV gene locus. Relationships with lipids, apolipoproteins, and premature coronary artery disease.

Data from various laboratories have indicated associations of various alleles determined by RFLPs within or adjacent to several apolipoprotein genes with abnormalities in plasma lipids and/or premature coronary artery disease (CAD). In order to assess such relationships we have examined allele frequencies of 8 different RFLPs within or adjacent to the apo A-I, C-III and A-IV gene complex on the long arm of chromosome 11 (MspI, 5' to the apo A-I gene; MspI, within the apo A-I gene; PstI, 3' to the apo A-I gene; SstI, 3' to the apo C-III gene; PvuII, within the apo C-III gene; PvuII, 5' to the apo C-III gene; XbaI, within the apo A-IV gene; and XbaI, 3' to the apo A-IV gene) in 202 patients with CAD (50% narrowing of one or more coronary arteries) prior to age 60 and 145 normal controls. None of the allele frequencies of these RFLPs were significantly different in cases as compared to controls. With regard to associations with plasma lipids and apolipoprotein levels, the rare allele determined by the absence of the PstI site was associated with elevated triglyceride levels (P less than 0.05) in cases, but not in controls. In contrast, the rate MspI allele 5' to the apo A-I gene was associated with elevated triglyceride levels (P less than 0.05) in controls but not in cases. In both cases and controls, subjects with the uncommon SstI allele had triglyceride levels that were 9 and 38% higher than in those without this allele. These differences were significant (P less than 0.05) only in controls. Our data indicate that the rare allele determined by the SstI site within this gene complex deserves further study in order to understand its association with elevated triglycerides in Caucasian populations. However, at the present time all these DNA markers lack sufficient specificity to be clinically useful for CAD risk assessment.     

Apolipoprotein B gene variants are involved in the determination of serum cholesterol levels: a study in normo- and hyperlipidaemic individuals

We have investigated the frequencies of 3 restriction fragment length polymorphisms (RFLPs) of the apolipoprotein B (apo B) gene in normo- and hyperlipidaemic individuals. In individuals with type III hyperlipidaemia, the allele frequency for the RFLP detected with XbaI was significantly different from the allele frequency in normolipidaemic individuals and in those with other types of hyperlipidaemia. No significant difference in allele frequency was found among these groups for the RFLPs detected with MspI or EcoRI. Within a sample of 62 normolipidaemic individuals, homozygotes for the X2 allele (cutting site) of the XbaI RFLP had a significantly higher serum cholesterol level than homozygotes for the XI allele, with individuals of the genotype X1X2 having an intermediate value (X2X2 mean 5.71 mmol/l, X1X1 mean 4.81 mmol/l, X1X2 mean 5.30 mmol/l). There were also significant differences in serum triglyceride levels in individuals with different XbaI genotypes. In these normolipidaemic individuals there was no correlation between the EcoRI and MspI RFLP genotypes and levels of any serum lipid variable. Information from the XbaI and EcoRI RFLPs was used in conjunction to define apo B haplotypes. These haplotypes are a more precise measure of the genotypic variation, and they explain a greater fraction of the serum cholesterol and triglyceride levels than the single-site polymorphisms considered separately. This study suggests that variations in the gene for apo B are associated with the determination of serum cholesterol and triglyceride levels both in patients with type III hyperlipidaemia and in the normal population.     

Apolipoprotein A-I gene polymorphisms: frequency in patients with coronary artery disease and healthy controls and association with serum apo A-I and HDL-cholesterol concentration

We have investigated the association between serum high density lipoprotein-cholesterol (HDL-C) and apo A-I concentration and the PstI and XmnI restriction fragment length polymorphisms of the apolipoprotein AI-CIII-AIV multigene complex. Two groups of subjects were examined. The first comprised 174 unrelated male patients under 60 years of age with angiographic evidence of coronary artery disease (CAD). Of this group 34 were non-North European. The second group consisted of 104 unrelated healthy male North European subjects aged under 60 and free from demonstrable CAD, who attended a health screening clinic in London. For the PstI polymorphism, the frequency of the rarer P2 allele was 0.12 in both the North European and non-North European patients and this was higher than in the control group (P2 frequency 0.06, P less than 0.05). Healthy individuals with the genotype P1P2 had higher levels of apo A-I but similar levels of HDL-C compared to those with the genotype P1P1. However, CAD patients with the genotype P1P2 had lower serum levels of apo A-I and significantly lower serum levels of HDL-C compared to those with the genotype P1P1 (0.85 mmol/l vs. 1.0 mmol/l, P less than 0.05). The allele frequencies of the XmnI polymorphisms were not significantly different in the control group and the group of North European patients, although within the sample of non-North European patients, the frequency of the X2 allele was significantly higher than that found in the North European controls (0.26 vs. 0.09). Patients with the genotype X1X2 had a higher mean serum concentration of HDL-C and apo A-I compared with patients with the genotype X1X1 (1.14 and 0.93 mmol/l for HDL-C, P less than 0.05; 147 and 123 mg/dl for apo A-I, P less than 0.05). Associations between HDL-C and apo A-I levels and PstI and XmnI genotype were similar in patients taking and not taking beta-blockers. The data show that genetic variation in the apo AI-CIII-AIV gene cluster is associated with coronary artery disease although only weakly, and suggest that the mechanism of this association may operate through an effect in determining the serum concentration of apo A-I and HDL-cholesterol.     

Sequence polymorphisms in the apolipoprotein(a) gene and their association with lipoprotein(a) levels and myocardial infarction. The ECTIM Study.

Lp(a) concentrations are largely determined by apo(a) isoform size, but several studies have shown that apo(a) isoforms could not entirely explain the increase of Lp(a) levels observed in patients with coronary heart disease (CHD). Since up to 90% of the variance in Lp(a) levels has been suggested to be attributable to the apo(a) locus, the hypothesis that polymorphisms of the apo(a) gene other than size could contribute to the increase of Lp(a) levels in CHD patients must be considered. This hypothesis was tested in the ECTIM Study comparing 594 patients with myocardial infarction and 682 control subjects in Northern Ireland and France. In addition to apo(a) phenotyping, five previously described polymorphisms of the apo(a) gene were genotyped: a (TTTTA)n repeat at position -1400 from the ATG, a G/A at -914, a C/T at -49, a G/A at -21 and a Met/Thr affecting amino acid 4168. As reported earlier [Parra HJ, Evans AE, Cambou JP, Amouyel P, Bingham A, McMaster D, Schaffer P, Douste-Blazy P, Luc G, Richard JL, Ducimetiere P, Fruchart JC, Cambien F. A case-control study of lipoprotein particles in two populations at contrasting risk for coronary heart disease. The ECTIM study. Arterioscler Thromb 1992; 12:701-707], mean Lp(a) levels were higher in cases than in controls (20.7 vs 14.6 mg/dl in Belfast, 17.2 vs 8.9 mg/dl in France, P < 0.001 for case-control and population differences). In the present study, mean apo(a) isoform size differed significantly between cases and controls (25.7 vs 26.6 kr in Belfast, 25.9 vs 27.4 kr in France, P < 0.001 for case-control and P = 0.13 for population difference). After adjustment for apo(a) isoforms, Lp(a) levels remained significantly higher in cases than in controls (difference, 4.6 mg/dl; P < 0.001). Genotype and allele frequencies did not differ significantly between cases and controls for any of the five polymorphisms studied. The five polymorphisms were in strong linkage disequilibrium and had a combined heterozygosity of 0.83. In multivariate regression analysis adjusted for apo(a) isoforms, only the (TTTTA)n polymorphism was significantly associated with Lp(a) levels; it explained 4.5% of Lp(a) variability in cases and 3.1% in controls. The Lp(a) case/control difference was not reduced after taking into account the (TTTTA)n effect. We conclude that the increase of Lp(a) levels observed in MI cases, and which was not directly attributable to apo(a) size variation, was not related to the five polymorphisms of the apo(a) gene considered.     

Relationship between gene polymorphisms and prevalence of myocardial infarction among diabetic and non-diabetic subjects

This study was aimed to examine cholesteryl ester transfer protein (CETP), apolipoprotein AI and CIII gene polymorphisms, and to verify whether these genetic determinants are associated with the prevalence of myocardial infarction (MI) or type 2 diabetes. The TaqIB restriction fragment length polymorphism (RFLP) in intron I of the CETP gene, the MspI in the third intron of the APOAI gene, and also SstI in the 3' untranslated region of the APOCIII gene were determined using standard methods. The prevalence of these polymorphisms was compared between diabetic (n = 119), and non-diabetic (n = 100) middle-aged individuals of both sexes. We found a higher prevalence of the B2B2 genotype of the CETP gene among diabetics than that observed in non-diabetics (P < 0.05), and a lower prevalence of this genotype among patients with previous MI (P < 0.02). The MspI polymorphisms of the APOAI gene showed that M1++ genotype was found mainly in diabetic patients (P < 0.04). Conversely, the SstI polymorphism of APOCIII gene was not significantly associated with either MI or diabetes. Therefore, among these genetic polymorphisms, TaqIB of CETP and MspI of apolipoprotein AI appeared to help significantly to identify diabetic individuals. In particular, the former may have an additional role in the primary prevention of coronary disease.     

Restriction fragment length polymorphisms in the apo B gene in relation to coronary artery disease

We have determined the frequencies of the alleles at the EcoRI (E), XbaI (X) and PvuII (P) polymorphic restriction sites in the apo B gene in 124 white men with coronary artery disease (CAD) and in 146 white men free from CAD. The frequencies of the E- (restriction site absent) and X- alleles were both significantly higher in normocholesterolaemic men with CAD than in those without CAD, but the frequency of the P+ allele (restriction site present) was similar in the 2 groups. The frequency of the E- allele was significantly higher in CAD men with hypertriglyceridaemia than in normal men without hypertriglyceridaemia. In the normocholesterolaemic men without CAD, the mean serum cholesterol concentration was higher in those with genotype X++ than in those with genotype X--. Mean serum LDL-apo B and LDL-cholesterol concentrations did not differ significantly between men with different XbaI or EcoRI genotypes. Serum apo A-I levels differed significantly between normal men with different XbaI genotypes. Serum HDL-cholesterol levels differed significantly between CAD men with different XbaI genotypes. These results suggest that in white men the E- and X- alleles are in linkage disequilibrium with a nearby allele that is causally related to CAD. It is also possible that the amino acid substitution at position 4154 in apo B, brought about by the nucleotide change responsible for the EcoRI polymorphism, has a direct effect on the atherogenicity of LDL.     

Apolipoproteins AI/B/E gene polymorphism and their plasma levels in patients with coronary artery disease in a tertiary care-center of Eastern India

AimThe present study was designed to investigate whether the three-apolipoprotein (AI, B, E) gene polymorphisms were related to alter their plasma protein levels and hence associated to coronary artery disease (CAD).MethodsWe determined distribution of MspI apo AI, EcoRI apo B, HhaI apo E gene polymorphisms, plasma apolipoproteins and lipids levels among 150 patients having CAD admitted to the Department of Cardiology, N.R.S. Medical College & Hospital, Kolkata, India during June 2010–June 2012 and 150 age sex matched healthy controls.ResultsWe found that ApoAI concentration of studied population was significantly different in each genotypes of ?75 G/A apo AI (p < 0.0001) gene polymorphism. A significant association was found in multivariate analysis for the genotypes with apo E4 allele [odds ratio (OR): 3.639; 95% confidence interval (CI): 1.019–12.995, p = 0.040] with four conventional risk factors (i.e. smoking, low-density lipoprotein, ApoAI and ApoB) with CAD. In contrast E2 allele has reverse effect, but the genotypes with apo E2 allele was no longer significant in the multivariate model (OR: 1.788; 95% CI: 0.400–8.001, p = 0.447) where as being significant in univariate analysis (OR: 0.219; 95% CI: 0.087–0.552, p = 0.001).ConclusionsOur findings suggest that the polymorphisms apo AI MspI and apo B EcoRI do not seem to affect CAD. But the genotype with E4 allele of apo E gene independent of other risk factors is associated with this disease.     

对氧磷酶基因多态性及血浆同型半胱氨酸硫内酯复合物水平与冠心病的关系

目的探讨对氧磷酶(PON)基因多态性(PON1 T-107C、PON2 C311S)及血浆同型半胱氨酸(Hcy)、同型半胱氨酸硫内酯(HTL)复合物水平与冠心病发病的关系。方法对203例经冠状动脉造影证实为冠心病的患者及117例经冠状动脉造影证实无冠状动脉病变的对照者进行研究,采用竞争性 ELISA 法测定血浆 HTL 复合物水平;采用高压液相色谱法测定血浆 Hcy 的水平;采用多聚酶链反应-限制性内切酶片段长度多态性(PCR-RFLP)分析 PON 基因中 PON1 T-107C 和 PON2 C311S基因多态性。结果冠心病组血浆 Hcy 和 HTL 复合物水平明显高于对照组(P<0.01);PON1 T-107C 基因型与等位基因频率分布在冠心病组与对照组间比较差异无统计学意义(P>0.05);而PON2 C311S 的 SS 基因型分布在冠心病组低于对照组(P<0.05),但等位基因频率分布两组间差异无统计学意义(P>0.05);当两位点的等位基因 T、S 同时出现时(即 CT/TF+CS/SS 基因型)血浆 Hcy及 HTL 复合物水平较 CC+CS/CC 或 CT+CC 基因型明显降低[Hcy(11.83±4.76)μmol/L 与(15.32±10.32)μmol/L;HTL(24.36±9.30)U/ml 与(32.05±10.44)U/ml],差异有统计学意义(P<0.05)。冠心病合并2型糖尿病组与冠心病无糖尿病组及对照组相比,PON2基因型分布差异有统计学意义,冠心病合并2型糖尿病患者中 C 等位基因频率明显增高(P<0.05)。结论血浆 Hcy 和 HTL 复合物水平升高可能是冠心病发病的独立危险因素,PON1 T 等位基因和 PON2 S 等位基因同时出现可能在动脉粥样硬化形成过程中起到保护作用,而 PON2 C311S 多态性的 C 等位基因存在可能与冠心病患者合并2型糖尿病的几率增高相关。     

血管紧张素转换酶和血管紧张素受体基因多态性与冠心病的关系

目的　探讨深圳地区冠心病 (CAD)与血管紧张素转换酶 (ACE)基因与血管紧张素 的 1型受体 (AT1R)基因多态性的关系。方法　分别采用 PCR及 PCR- Afl II酶切法 ,检测 89例 CAD患者和 14 8例健康对照的 ACE和AT1R基因型。结果　 CAD组与对照组比较 ,ACE DD基因型频率 (2 4 .7%比 8.1% ,P<0 .0 1)及 D型等位基因频率 (4 4 .4 %比 33.4 % ,P<0 .0 5 )均为升高。 CAD组与对照组 AT1R基因型频率分布无显著性差异 (P>0 .0 5 )。携带 AT1R C等位基因的个体患 CAD的风险与其同时携带 ACE DD基因型无关 (P>0 .0 5 )。结论　深圳地区CAD的发生和发展可能与 ACE基因 I/ D多态性有关 ,而与 AT1R基因 A116 6 C多态性无关     

The T allele of the missense Glu(298)Asp endothelial nitric oxide synthase gene polymorphism is associated with coronary heart disease in younger individuals with high atherosclerotic risk profile.

AIMS: Nitric oxide (NO) plays a protective role during atherogenesis. In the endothelium, NO is synthesised by the constitutive NO synthase (ecNOS). We analysed the relation of the ecNOS Glu(298)Asp and 4a/b gene polymorphisms to coronary artery disease (CAD) and myocardial infarction (MI) in a population of 3250 German subjects (533 healthy controls and 2717 individuals who underwent coronary angiography). RESULTS: Although in the total sample, the ecNOS T allele was not associated with the risk of CAD (P=0.054) and the extent of this disease (P=0.078), a restriction to younger individuals (age相似文献   

Plasma apolipoprotein A-I, A-II, B, E and C-III containing particles in men with premature coronary artery disease

Lipoprotein (Lp) cholesterol and apolipoproteins (apo) A-I and B levels have been shown to be better markers for the presence of coronary artery disease than total cholesterol. In this study, we determined the plasma levels of lipoprotein particles containing apo A-I only (LpA-1), apo A-I and A-IL (LpA-I:A-1I), apo B and C-III (LpB:C-III) and apo B and E (LpB:E) in 145 patients with coronary artery disease (mean age ± SD, 51 ± 7 years) and 135 healthy control men (mean age 49 ± 11 years). Patients with CAD had lower high density lipoprotein (HDL) cholesterol and apo A-I levels and higher triglycerides and apo B levels than controls. In patients with CAD, LpA-I (0.341 ± 0.093 vs. 0.461 ± 148 g/1) and LpA-1:A-II (0.694 ± 0.171 vs. 0.899 ± 0.148 g/1) were lower, whereas LpB:E (0.372 ± 0.204 vs. 0.235 ± 0.184 g/1) were higher than in controls (cases vs. controls, all P < 0.005). No significant differences were observed for LpB:C-III (0.098 ± 0.057 vs. 0.107 ± 0.061 g/1, p = 0.235) particles. Discriminant analysis indicates that LpA-II:A-I, LpE:B, LpA-I, and triglycerides best differentiate between cases and controls. Plasma apo C-III (0.027 ± 0.008 vs. 0.036 ± 0.020 g/1) and E (0.040 ± 0.015 vs. 0. 055 ± 0.029 g/1) were lower in the CAD group (P < 0.001). The finding that apo C-III and E levels are lower in the CAD patients relate to the fact that in our patients, HDL particles are the main carriers of apo E and C-III and that in addition to HDL-cholesterol, the protein component of HDL particles are reduced in CAD. We conclude that apo B, LpB:E but not LpB:C-III containing particles are increased in patients with CAD and that apo A-I containing particles, with or without apo A-II are reduced in patients with CAD. In addition, HDL-cholesterol and associated apolipoproteins (A-I, A-11, C-III and E) are reduced in CAD.     

Apolipoprotein B gene polymorphisms are associated with lipid levels in men of South Asian descent.

Three polymorphic sites of the apolipoprotein B gene - the insertion/deletion signal peptide, XbaI and EcoRI sites - were examined in a sample of 107 healthy men and in 46 men with evidence of coronary heart disease selected from a large population survey of South Asians aged 40-69 in London, U.K. There were no significant differences in allele frequencies between cases and controls. Frequencies of the ins (insertion) and X- (absence of XbaI cutting site) alleles were higher in South Asians than in Europeans studied previously (South Asians versus Europeans ins: 0.80 vs. 0.68, P less than 0.025; X-: 0.71 vs. 0.47-0.56, P less than 0.001). The del allele was associated with higher levels of total cholesterol (P less than 0.05) and the X+ allele with lower levels of HDL cholesterol (P less than 0.05), and thus both polymorphisms were associated with differences in the ratio of HDL cholesterol to total cholesterol (ins/del, P less than 0.01; XbaI, P less than 0.001). Mean waist-hip girth ratio was lower in the 10 men homozygous for the X+ allele than in the 42 men with X-/X+ and 55 men with X-/X- genotypes; the means (+/- SEM) were 0.92 +/- 0.02, 0.97 +/- 0.01 and 0.96 +/- 0.01 respectively (P = 0.03). These data suggest that genetic variation in linkage disequilibrium with the XbaI and ins/del polymorphisms of the apo B gene contributes to the determination of total cholesterol and HDL cholesterol levels and possibly to obesity in South Asians.     

屏氧酶192基因多态性与血脂及心肌梗死的关系

目的 :研究屏氧酶 192谷氨酸 /精氨酸 (PON192 ,Gln/Arg)基因多态性与血浆脂质水平及心肌梗死(MI)的关系。方法 :应用多聚酶链反应 限制性内切酶片段长度多态性 (PCR RFLP)技术检测 132例MI与相同例数正常人PON 192基因多态性 ,血浆脂质水平测定按常规进行。结果 :发现PON 192基因型有三种 ,即纯合子突变型 (BB) ,杂合子突变型 (AB) ,正常型 (AA)。正常对照组中AA型频率 17.6 % ,AB型频率 4 5 .3% ,BB型频率37.1%。A等位基因频率为 4 5 .2 % ,B等位基因频率为 5 4 .8%。MI组AA型频率 10 .2 % ,AB型频率 4 1.3% ,BB型频率 4 8.5 %。A等位基因频率为 30 .7% ,B等位基因频率为 6 9.3%。两组对比等位基因频率差异有显著性意义。高密度脂蛋白水平在两组间差异无显著性意义。结论 :MI患者PON 192 ,B等位基因频率明显高于正常对照组 ,说明PON 192基因突变与MI的发生密切相关     

Frequency of and interaction between polymorphisms in the beta3-adrenergic receptor and in uncoupling proteins 1 and 2 and obesity in Germans

OBJECTIVE: To determine the role of polymorphisms in the genes for beta3-adrenergic receptor (beta3-AR) and in uncoupling proteins 1 and 2 (UCP-1, UCP-2) in obesity. DESIGN: Association study with three polymorphisms and obesity. SUBJECTS: Two hundred and thirty-six morbidly obese patients who underwent gastric banding surgery, 381 patients from the medical clinic and 198 healthy blood donors. MEASUREMENTS: The frequencies of the W64R in beta3-AR, the 3826A-->G in UCP-1 and the 45bp insertion in the 3 untranslated region of exon 8 in UCP-2 polymorphisms were determined. RESULTS: There were no significant differences in the frequencies of the beta3-AR and UCP-1 polymorphisms between obese (body mass index, BMI > 30 kg/m2) and lean subjects. Lean, but not obese, carriers of the R allele of beta3-AR had a significantly higher BMI. The mean age of obese subjects (excluding diabetics) who were carriers of the G allele of the UCP-1 polymorphism, 36y, was significantly younger than wild-type, 40y (P= 0.007). This effect was not seen in lean subjects. The effect of the G allele on the mean age of obese subjects was more apparent in subjects who were also carriers of the R allele of the beta3-AR polymorphism. The frequency of the ins allele of UCP-2 was significantly higher in obese subjects, 0.31, than in lean, 0.24 (P= 0.002) and carriers of the ins allele had a significantly higher BMI, 38 vs 35 (P= 0.005). There was no association between any of the polymorphisms and type II diabetes. CONCLUSION: In a German population, there was no association between the W64R in beta3-AR or the 3826A-->G in UCP-1 polymorphisms and obesity. However, they act synergistically to accelerate the development of obesity. The 45bp insertion in the 3 untranslated region of exon 8 in UCP-2 polymorphism is associated with obesity.     

载脂蛋白E基因多态性对血脂水平的影响及与冠状动脉狭窄的关系

为探讨载脂蛋白E基因多态性对血脂水平的影响及与冠状动脉狭窄程度的关系 ,采用聚合酶链反应—限制片段长度多态性对 95例冠心病患者和 46例正常对照者载脂者蛋白E基因型进行分析 ,同时测定血脂及载脂蛋白B水平。并根据冠状动脉受累支数不同将冠心病患者分为冠状动脉多支病变组和单支病变组。结果显示 ,5 5例冠状动脉病变多支组和 40例冠状动脉单支病变组E3/ 4基因型和ε4等位基因频率均高于对照组 (P <0 .0 1) ,且多支病变组E3/ 4基因型和ε4等位基因频率高于单支病变组 (P <0 .0 5 )。与E3/ 3及E2 / 3基因型比较 ,E3/ 4基因型者有较高的总胆固醇、低密度脂蛋白胆固醇和载脂蛋白B水平及较低的高密度脂蛋白胆固醇水平。与对照组比较 ,冠心病组E3/ 4基因型升高总胆固醇、低密度脂蛋白胆固醇和载脂蛋白B的作用及降低高密度脂蛋白胆固醇的作用更明显。表明载脂蛋白E基因多态性影响血胆固醇代谢 ,ε4等位基因与冠心病危险性增加有关 ,ε4等位基因频率升高的冠心病者冠状动脉受累支数加重 ,推测ε4等位基因可能与冠状动脉狭窄程度存在内在联系。     

Polymorphisms of the endothelin-A and -B receptor genes in relation to blood pressure and myocardial infarction: the Etude Cas-Témoins sur l'Infarctus du Myocarde (ECTIM) Study

Endothelin-1 is a potent vasoconstrictor that has also mitogenic properties, stimulating the synthesis and secretion of several vasoactive molecules. There is much evidence to suggest that endothelin-1 might be involved in the pathogenesis of hypertension, atherosclerosis, and ischemic heart disease. Endothelin-1 exerts its effects through at least two receptors, ET(A) and ET(B), which are encoded by different genes and have separate tissue distributions and biologic properties. The objective of this study was to identify polymorphisms of the ET(A) and ET(B) receptor genes and to study their association with myocardial infarction (MI) and blood pressure. The coding regions and 1.3 kb upstream of the ET(A) and ET(B) receptor genes were explored by polymerase chain reaction/single strand conformation polymorphism. Six polymorphisms were found in the ET(A) receptor gene and three in the ET(B) receptor gene. Most of these polymorphisms were frequent. Associations between the detected polymorphisms, blood pressure, and MI were examined in the ECTIM study, a multicenter study comparing 652 patients having survived an MI and 773 controls from Belfast (Northern Ireland) and France. Alleles at the different polymorphic sites were similarly distributed in patients with MI and controls. Allele frequencies were similar in both countries, except for the ET(A)/-231 G allele, which appeared more frequently in France than in Belfast (P < .01). The mean systolic and diastolic blood pressure levels did not significantly differ between genotypes. However, a C/T substitution located in the nontranslated part of exon 8 of the ET(A) receptor gene (ET(A)/EX8nt1363) was associated with pulse pressure (P < .005). These results do not support an involvement of the endothelin receptor genes in a predisposition to MI or the determination of blood pressure levels, but suggest that a polymorphism of the ET(A) receptor gene might influence the pulse pressure. This result will have to be confirmed in other studies.     

Angiotensin-converting enzyme and apolipoproteins genes polymorphism in coronary artery disease

BACKGROUND: Association between angiotensin-converting enzyme (ACE) as well as apolipoprotein (apo) AI, B, and E polymorphisms and dyslipidemia and coronary artery disease (CAD) is controversial. HYPOTHESIS: This study assessed the distribution of ACE insertion/deletion, apo AI A/G mutation, apo B signal peptide insertion/deletion, apo B XbaI restriction fragment length, and apo E polymorphisms in 388 nondiabetic patients. METHODS: The study population included 112 patients with stable CAD, 139 patients with acute myocardial infarction (AMI), and 137 age-matched control subjects. RESULTS: Univariate analysis showed higher prevalence of XbaI X+/X+ genotype in patients with CAD (p = 0.02). Angiotensin-converting enzyme and apo polymorphisms were not associated with lipid levels or severity of CAD. When all genotypes known to be related to CAD; such as ACE DD, apo AI GG, apo B del/del, and XbaI X+X+, and E4 allele of apo E, were pooled, again no significant differences among groups were seen. Multivariate regression analysis disclosed traditional risk factors and elevated levels of apo B for men and reduced levels of apo AI for women as independent variables for CAD. CONCLUSIONS: In addition to traditional coronary risk factors, apo B and AI could be considered predictors of CAD. No association between either form of CAD and polymorphisms was noted.