Allelic expression of APOE in human brain: effects of epsilon status and promoter haplotypes

The epsilon4 haplotype of APOE is the only undisputed genetic risk factor for late-onset Alzheimer's disease (LOAD). It has been proposed that at least two other polymorphisms in the promoter of the APOE gene (-219G>T and -491A>T) might also contribute to disease susceptibility, and modulate the impact of structural changes in the ApoE protein, by altering its expression. In order to assess the extent of cis-acting influences on APOE expression in human brain, highly quantitative measures of allele discrimination were applied to cortical RNA from individuals heterozygous for the epsilon alleles. A small, but significant, increase in the expression of epsilon4 allele was observed relative to that of the epsilon3 and epsilon2 alleles (P<0.0001). Similar differences were observed in brain tissue from confirmed LOAD subjects, and between cortical regions BA10 (frontopolar) and BA20 (inferior temporal). Stratification of epsilon4/epsilon3 allelic expression ratios according to heterozygosity for the -219G>T promoter polymorphism revealed significantly lower relative expression of haplotypes containing the -219T allele (P=0.02). Our data indicate that, in human brain, most of the cis-acting variance in APOE expression is accounted for by the epsilon4 haplotype, but there are additional, small, cis-acting influences associated with promoter genotype.     

Association of APOE epsilon2/epsilon3/epsilon4 and promoter gene variants with dementia but not cardiovascular mortality in old age.

The common apolipoprotein E (APOE) alleles epsilon2, epsilon3, and epsilon4 are associated with the risk of dementia and cardiovascular disease. Recently, two functional variants (- 219G/T and -491A/T) were identified in the promoter of the APOE gene that enable a further characterization of the role of the APOE locus in disease. We investigated the contribution of these APOE gene variants to dementia and cardiovascular mortality in old age using a population-based cohort of 648 subjects aged 85 years and over (Leiden 85-Plus Study). Genotypes containing an APOE epsilon4 allele were associated with a 4.1-fold (95% CI, 2.2-7.7) increased risk of dementia as compared to the epsilon3/epsilon3 genotype in old subjects. Moreover, homozygosity for the -219T allele was found to be associated with a 2.4-fold (95% CI, 1.0-5.8) increased risk independently of epsilon2 and epsilon4; the -491A/T variant was not associated with dementia. Over a 10-year follow-up period, the risk of cardiovascular mortality was not increased among epsilon4 carriers (RR, 0.6; 95% CI, 0.4-1.0) or -219T homozygous subjects (RR, 1.1; 95% CI, 0.7-1.7), nor did it decrease among -491T homozygous subjects (RR, 1.4; 95% CI, 0.6-3.1). In conclusion, both the APOE epsilon2/epsilon3/epsilon4 and the -219G/T variant were identified as risk factors for dementia but not cardiovascular mortality in old age. Our results support the hypothesis that both the isoform and the amount of APOE may influence the risk of dementia. Furthermore, they emphasize that variation at the APOE locus has a higher impact on the risk of dementia than on the risk of cardiovascular disease in old age.     

The CDC2 I-G-T haplotype associated with the APOE epsilon4 allele increases the risk of sporadic Alzheimer's disease in Sicily

The cell division cycle 2 (CDC2) gene is a candidate susceptibility gene for Alzheimer's disease (AD). We investigated the CDC2 genotype, and allele and haplotype frequencies in AD patients and matched controls, distinguishing between apolipoprotein E (APOE) epsilon4 allele carriers and non-carriers. APOE epsilon4 is an established predictor of AD risk. APOE and CDC2 genotypes were examined in 109 sporadic AD patients and in 110 healthy age- and sex-matched controls from Sicily. The epsilon4 allele of APOE was predictive of AD risk in our study group (odds ratio: 5.37, 95% CI 2.77-10.41; P<0.0001). Genotype and allele frequencies of the three tested CDC2 polymorphisms (Ex6+7I/D, Ex7-15 G>A, Ex7-14 T>A) were not significantly different between AD patients and controls. However, a significant different distribution of a specific CDC2 haplotype (I-G-T) was found between AD patients and controls when analyzing APOE epsilon4-positive subjects (P=0.0288). Moreover, the combined presence of the I-G-T haplotype and the epsilon4 allele almost doubled the risk of AD (odds ratio: 10.09, 95% CI 3.88-26.25; P<0.0001) compared to carriers of epsilon4 alone. This study suggests that the I-G-T haplotype of the CDC2 gene increases the risk of AD in APOE epsilon4 carriers.     

Independent association of an APOE gene promoter polymorphism with increased risk of myocardial infarction and decreased APOE plasma concentrations-the ECTIM study

Apolipoprotein E (APOE) is a major protein in lipid metabolism existing in three common isoforms: APOE2, -3 and -4. The varepsilon4 allele of the APOE gene ( APOE ) coding for the APOE4 isoform is associated with an increased risk of myocardial infarction (MI) and of Alzheimer's disease (AD). Recently, several polymorphisms in the APOE regulatory region have been reported. Some of these have been associated with AD and modified APOE allelic mRNA expression in AD brains. Here, we have investigated whether three of these promoter polymorphisms (-491AT, -427CT and -219GT) can also modify cardiovascular risk. The hypothesis was tested in a large multicentre case-control study of MI, the ECTIM Study, on 567 cases and 678 controls. Among the three APOE promoter polymorphisms tested, only the-219T allele was associated with a significantly increased risk of MI (OR = 1.29, 95% CI: 1.09-1.52, P < 0.003) and the effect was shown to be independent of the presence of the other mutations, including the APOE epsilon2/epsilon3/epsilon4 polymorphism. Moreover, the-219T allele greatly decreased the APOE plasma concentrations in a dose-dependent manner ( P < 0.008). These data indicate that the-219GT polymorphism of the APOE regulatory region emerges as a new genetic susceptibility risk factor for MI and constitutes another common risk factor for both neurodegenerative and cardiovascular diseases.     

Apolipoprotein E gene promoter (–219G/T) polymorphism is associated with premature coronary heart disease

The relationship of two apolipoprotein (apo) E gene polymorphisms and coronary heart disease (CHD) was investigated in 118 Finnish families with premature CHD and in 110 healthy control subjects. Affected siblings and probands with premature CHD had higher frequencies of the T allele of the -219G/T promoter polymorphism and the epsilon 4 allele (genotypes epsilon 4/3 or epsilon 4/4) of the apo epsilon 2/epsilon 3/ epsilon 4 polymorphism than those of healthy control subjects. Additionally, when the two apo E gene polymorphisms were combined, affected siblings and probands had a higher frequency of the -219T allele and the epsilon 4 allele combinations than did healthy controls. The -219T and the epsilon 4 alleles both separately and together were associated with higher levels of 2-h glucose in an oral glucose tolerance test. These results indicate that the two polymorphisms of the apo E gene have similar effects on the risk of coronary atherosclerosis in families with premature CHD. This risk was not explained by the effect of apo E gene polymorphisms on cholesterol metabolism, but their effect on cardiovascular risk factor clustering with insulin resistance may be of importance. We conclude that in addition to the epsilon 4 allele, also the -219G/T promoter polymorphism of the apo E gene is associated with early onset CHD.     

PDCD1 polymorphism amplifies the predisposing effect conferred by CTLA4 polymorphism in chronic hepatitis B virus infection

Programmed cell death 1 (PDCD-1) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) both negatively regulate the T-cell response in chronic hepatitis B virus (HBV) infection. This study determined genotypes of PDCD1 -606 G/A and +8669 G/A and CTLA4 -318 C/T and +49 A/G polymorphisms in 172 chronic HBV patients and 145 healthy controls and analyzed the interaction between these polymorphisms of the 2 genes. The results indicated that carriage of the PDCD1 +8669 A allele was increased in HBV patients carrying the CTLA4 -318 CC genotype and carrying the CTLA4 +49 AA genotype compared with controls carrying the CTLA4 -318 CC genotype (80.2% vs 64.8%, p = 0.002, odds ratio [OR] = 2.202, 95% confidence interval [95% CI] = 1.326-3.656) and carrying the CTLA4 +49 AA genotype (18.6% vs 9.7%, p = 0.024, OR = 2.139, 95% CI = 1.093-4.187), respectively. More obviously, carriage of the PDCD1 +8669 AA genotype was significantly increased in HBV patients carrying the CTLA4 +49 AA genotype compared with controls carrying the same CTLA4 +49 genotype (14.0% vs 3.4%, p = 0.001, OR = 4.541, 95% CI = 1.686-12.230). These results suggest that the PDCD1 +8669 A allele and AA genotype may amplify the predisposing effect conferred by the CTLA4 polymorphism through PDCD1 and CTLA4 gene interaction in chronic HBV infection.     

Polymorphisms in genes coding for mediators in the interleukin cascade and their effect on susceptibility to sarcoidosis in the Slovenian population

Sarcoidosis is a chronic inflammatory disease characterised by granulomatous inflammation in various organs. As genetic factors have been implicated in its aetiology, in our study we investigated whether the promotor polymorphisms in three genes coding for inflammatory mediators interleukin-6 (IL-6), interleukin-12 (IL-12), and interleukin-18 (IL-18) could be associated with susceptibility to sarcoidosis. The study sample consisted of 104 patients with sarcoidosis and 100 healthy control subjects. Following DNA isolation from peripheral blood the IL-6/-174G>C single nucleotide polymorphism (SNP), the IL-12B/4 bp insertion polymorphism, and the IL-18/-137G>C SNP were characterised by polymerase chain reaction. Our results showed an increased frequency of IL-6/-174C allele (p<0.01, OR=2.05, 95% CI=1.32-3.16), and also an increased genotype frequency of IL-6/-174 CC and CG carriers (p<0.01, OR=2.78, 95% CI=1.49-5.19) among sarcoidosis patients in comparison with healthy controls. Allele and genotype frequencies did not differ significantly between cases and controls for either the IL-12B/4 bp insertion polymorphism or for the IL-18/-137G>C polymorphism. In conclusion, we demonstrated that the -174G>C promotor polymorphism in the IL-6 gene may be a risk factor for sarcoidosis.     

Association of TIM4 promoter polymorphism −1419G>A with childhood asthma in a Chinese Han population

TIM4, which is expressed on dendritic cells and macrophages, plays an important role in the proliferation of T helper type 2 (Th2) cells. Asthma, as a complex genetic disease, is thought to arise from the development of a Th2-lymphocyte-predominant immune response. To evaluate the effects of the promoter polymorphisms (-1419G>A and -1609G>A) in TIM4 on asthma susceptibility, case-control and family-based association studies were conducted by polymerase chain reaction and restriction fragment length polymorphism. Our results showed that TIM4 -1419G>A polymorphism was associated with asthma susceptibility in our study population (χ²= 9.88, P < 0.001, OR = 1.91, 95% CI 1.37–2.64). The -1419A/A and -1419A/G genotypes were observed more common in asthmatic group (6.3%, 41.8%) than in control group (1.7%, 29.3%). No significant difference was found in genotype and allele frequencies of TIM4 -1619G>A polymorphism between asthmatic and control groups. No association between the two SNPs and total serum IgE levels, lung function was observed. In conclusion, the present findings suggest that TIM4 -1419G>A polymorphism might be the genetic factor for the risk of childhood asthma in Chinese Han population.     

TNF polymorphisms in Alzheimer disease and functional implications on CSF beta-amyloid levels

Alzheimer disease (AD), vascular dementia, and stroke are all associated with inflammation though their respective initiating factors differ. Recently a polymorphism in the proinflammatory cytokine tumor necrosis factor (TNF), in association with apolipoprotein E (APOE), was reported to increase AD risk. Two SNPs, rs1799724 (-850C>T; NT_007592.14:g.22400733C>T) and rs1800629 (-308G>A; [NT_007592.14:g.22401282G>A]), and the APOE polymorphism were genotyped in 506 patients with sporadic AD and in 277 cognitively healthy controls. In a subset of 90 individuals we also investigated whether these SNPs exerted any functional effects on cerebrospinal fluid (CSF) beta-amyloid (Abeta) levels. The frequency of the rs1799724 genotypes and the rs1799724-T allele were significantly different in AD individuals (P=0.009; odds ratio [OR], 1.63; 95% confidence interval [CI], 1.13-2.34), while the rs1800629 SNP was not associated with AD. Significant interaction was observed between the rs1799724-T and APOE epsilon4 alleles in that the rs1799724-T allele significantly modified risk associated with possession of the epsilon4 allele only (epsilon4 in absence of rs1799724-T: OR, 2.92; 95% CI, 2.00-4.27; epsilon4 in presence of rs1799724-T: OR, 6.65; 95% CI, 3.26-13.55; P=0.03). Haplotyping analysis revealed a significant overrepresentation of an rs1799724-T/rs1800629-G haplotype in AD (P=0.012; OR, 1.60; 95% CI, 1.11-2.29), although to a lesser degree than rs1799724-T alone. Further, the rs1799724-T allele was found to be associated with lower levels of CSF Abeta42 (P=0.023), thus corroborating the genetic findings. Inheritance of the rs1799724-T allele appears to synergistically increase the risk of AD in APOEepsilon4 carriers and is associated with altered CSF Abeta42 levels. Further investigations are warranted to assess the significance of these novel findings.     

ApoE epsilon3-haplotype modulates Alzheimer beta-amyloid deposition in the brain

ApoE epsilon4 allele increases the risk of late-onset Alzheimer disease (AD) as well as the amount of beta-amyloid deposition in the brain. Because half of AD patients do not have ApoE epsilon4, it is important to search for other determinants of ApoE that modify AD risk. We tested whether the haplotype background of the most common ApoE allele, epsilon3, influences brain amyloid deposition or the risk of neuropathologically verified AD in a population-based sample of elderly Finns. To exclude the effects of ApoE protein polymorphism we focused these analyses on subjects homozygous for epsilon3. Haplotypes were defined using polymorphisms at positions - 491 and -219 of the ApoE promoter and at position +113 of intron-1. We found that epsilon3-haplotypes containing the promoter allele -219T were associated with reduced amyloid deposition and reduced risk of neuropathologically verified AD as compared to epsilon3-haplotypes containing -219G. The functional polymorphism(s) responsible for the haplotypic difference remains to be identified. These results indicate that there is significant allelic variation in the ApoE gene region, which modulates brain amyloid deposition and AD risk, independent of the ApoE protein polymorphism.     

135G>C and 172G>T polymorphism in the 5' untranslated region of RAD51 and sporadic endometrial cancer risk in Polish women

BACKGROUND : Despite advanced diagnostic and therapeutic procedures, endometrial cancer (EC) is still responsible for high morbidity and mortality of women. The genetic variability in RAD51 may contribute to the appearance and progression of various cancers including EC. AIM : We investigated the association of polymorphisms in the DNA repair genes RAD51 135G>C and 172G>T with endometrial cancer risk. MATERIAL AND METHODS : The genotypes of RAD51 135G>C and 172G>T polymorphism were determined by PCR-RFLP methods in endometrial tissue of 240 cancer subjects and 240 healthy subjects who served as controls. RESULTS : In the present work we demonstrated a significant positive association between the RAD51 C/C genotype and endometrial carcinoma, with an adjusted odds ratio (OR) of 13.0 (p < 0.0001). The distribution of genotypes for 135G>C SNP in endometrial cancer patients vs. controls was: 10% vs. 27% for GG, 13% vs. 58% for GC and 77% vs. 15% for CC genotype, respectively. Variant 135C allele of RAD51 increased the cancer risk (OR = 1.81; 95% CI 0.11-2.93, p = 0.022). The higher risk of EC occurrence was associated with the combined C135C-G172T genotype (OR = 7.69; 95% CI 3.45-17.12). CONCLUSION : The results indicated that the polymorphism 135G>C of the RAD51 gene may be positively associated with endometrial carcinoma in the Polish population. Further studies, conducted on a larger group, are required to clarify this point.     

Folate gene polymorphisms and the risk of Down syndrome pregnancies in young Italian women

Maternal impairments in folate metabolism and elevated homocysteinemia are known risk factors for having a child with Down syndrome (DS) at a young age. The 80G>A polymorphism of the reduced folate carrier gene (RFC-1) has been recently demonstrated to affect plasma folate and homocysteine levels, alone or in combination with the 677C>T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene. We performed the present study on 80 Italian mothers of DS individuals, aged less than 35 at conception, and 111 Italian control mothers, to study the role of the RFC-1 80G>A, MTHFR 677C>T, and MTHFR 1298A>C genotypes to the risk of a DS offspring at a young maternal age. When polymorphisms were considered alone, both allele and genotype frequencies did not significantly differ between DS mothers and control mothers. However, the combined MTHFR677TT/RFC-1 80GG genotype was borderline associated with an increased risk (OR 6 (CI 95%: 1.0-35.9), P = 0.05), and to be MTHF1298AA/RFC-1 80(GA or AA) was inversely associated with the risk (OR 0.36 (CI 95%: 0.14-0.96), P = 0.04). Present results seem to indicate that none of the RFC-1 80G>A, MTHFR 677C>T, and MTHFR 1298A>C polymorphisms is an independent risk factor for a DS offspring at a young maternal age; however, a role for the combined MTHFR/RFC-1 genotypes in the risk of DS pregnancies among young Italian women cannot be excluded.     

Association between VEGF polymorphisms (936c/t, -460t/c and -634g/c) with haplotypes and coronary heart disease susceptibility

Aim: Our aim was to investigate the association between single nucleotide polymorphisms (SNPs) of vascular endothelial growth factor (VEGF) and coronary heart disease (CHD) susceptibility in Chinese Han population. Methods: 144 CHD patients and 150 healthy individuals were enrolled in the study. Three SNPs (936C/T, -460T/C and -634G/C) of VEGF were chose and then were genotyped with Sequenom time-of-flight mass spectrometry (TOFMS). Odds ratio (OR) with 95% confidence interval (CI) were used to evaluate the association of genotypes and haplotypes and CHD susceptibility. Results: The frequencies of -460T/C CC genotype (13.6%) was found higher in the case group than that of control group (6.7%), which indicated that CC genotype was a risk factor for CHD (OR=2.50, 95% CI=1.10-5.68). Correspondently, the C allele appeared to increase the risk of CHD (OR=1.54, 95% CI=1.07-2.22). For -634G/C polymorphism, the risk of the CC genotype carrier for CHD increased 2.24 fold compared to the wild genotype. Moreover, -634G/CC allele was significantly associated with CHD susceptibility (OR=1.65, 95% CI=1.15-2.36). In addition, +936C/T CT genotype and C allele appeared to be a genetic-susceptibility factors for CHD (OR=2.43, 95% CI=1.44-4.10; OR=1.95, 95% CI=1.26-3.02). The haplotype analysis showed that T-C-T, C-C-C and C-G-C haplotypes all could increase the risk for CHD (OR: 2.43, 2.77 and 2.33). Conclusion: we concluded VEGF polymorphisms were associated with CHD susceptibility. Moreover, the haplotypes of T-C-T, C-C-C and C-G-C all could increase the risk for CHD.     

ABCB1 polymorphisms associated with osteonecrosis of the femeral head

Aims: This case-control study was conducted to investigate the relation of ATP-binding cassette subfamily B member 1 (ABCB1) C1236T and C3435T polymorphisms and non-traumatic osteonecrosis of the femeral head (ONFH). Methods: We gathered 113 ONFH patients and 116 controls in the study. The polymorphisms of ABCB1 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Odds ratio (OR) with 95% confidence interval (CI) were adopted to analyze the correlation between ABCB1 polymorphisms and ONFH. Results: In the study, we found that the frequency of C3435T TT genotype was much lower in case group, compared with that of controls (17.7% vs. 23.3%). Moreover, OR and 95% CI values indicated that C3435T TT genotype served as a protective factor for ONFH (OR=0.34, 95% CI=0.15-0.75). Meanwhile, the risk for the T allele carriers was much lower than C allele (OR=0.60, 95% CI=0.42-0.87). However, C1236T polymorphism showed no significant effects on the pathogenesis of ONFH. In the haplotype analysis, T-T haplotype appeared to be an inhibitor for ONFH (OR=0.45, 95% CI=0.23-0.87). Conclusions: Based on the results, ABCB1 polymorphisms were associated with the risk for ONFH.     

Evaluation of the CD14/-260 polymorphism and house dust endotoxin exposure in the Barbados Asthma Genetics Study

BACKGROUND: Both a functional promoter polymorphism in the gene encoding CD14 (C-260T) and exposure to endotoxin are believed to play key roles in modulating the immune response and expression of atopic disease. OBJECTIVE: We aimed to evaluate the role of the CD14 C-260T polymorphism in a population of African descent and to test for interaction between this genotype and house dust endotoxin (HDE) exposure on atopic phenotypes. METHODS: Asthmatic probands and their families were recruited as part of the Barbados Asthma Genetics Study. The C-260T polymorphism and two additional CD14 promoter markers (G-1461T, C-1721T) were genotyped. Endotoxin was measured in house dust samples. RESULTS: Using a Family-Based Association Test, the C-260T allele appeared to be protective against asthma ( z = -2.444; P = .015) and asthma severity ( z = -2.615; P = .009) under a recessive model. No significant associations were observed for the G-1461T and C-1721T markers both individually and in haplotypes. In a case-control analysis, the CD14 TT genotype was found to reduce risk of asthma compared with the CD14 CC/CT genotypes (odds ratio [OR], 0.26; 95% CI, 0.14-0.49) and was associated with lower asthma severity scores ( P < .002). The TT genotype might protect against asthma for individuals with low HDE (OR, 0.09; 95% CI, 0.03-0.24), but may be a risk factor for individuals with high HDE (OR, 11.66; 95% CI, 1.03-131.7), suggesting a gene-environment interaction. CONCLUSION: These data suggest that the CD14-260 polymorphism may play a role in controlling risk to atopic disease and underscore the importance of incorporating key environmental exposures into studies of genetic risk factors.     

Association between NOD2/CARD15 polymorphisms and coronary artery disease: a case-control study

Inflammation and immune response play an important role in the pathogenesis of atherosclerosis. In this prospective study we tested the hypothesis of whether polymorphic variations in the NOD2/CARD15 gene may influence the risk of developing clinically evident coronary artery disease (CAD). ARG702TRP, GLY908ARG, and Leu1007fsinsC NOD2/CARD15 polymorphisms were analyzed in 109 consecutive patients with angiographically documented CAD and in 109 age- and sex-matched healthy controls. The ARG702TRP, GLY908ARG, and Leu1007fsinsC polymorphisms were analyzed by polymerase chain reaction followed by restriction digestion. The prevalence of the Leu1007fsinsC polymorphism was significantly increased in CAD patients compared with controls (11.9% vs 1.8%; odds ratios (OR) 7.2, 95% confidence interval (95% CI) 1.5-32.9; p = 0.01), especially in those presenting with an acute coronary syndrome (OR 5.7; 95% CI 1.1-39.7; p = 0.034 vs stable angina). In CAD patients the frequency of GLY908ARG polymorphism was significantly lower (1.8% vs 6.4% in controls; OR 0.05, 95% CI 0.01-0.69; p = 0.031, at multivariable analysis) and the prevalence of the ARG702TRP polymorphism was higher compared with controls (10.1% vs 3.7%; OR 2.9, 95% CI 0.91-9.6; p = 0.07). We report in a Caucasian population that NOD2/CARD15 polymorphisms influence the development of clinically evident and angiographically documented coronary artery disease. In particular, the Leu1007fsinsC polymorphism was associated with an increased risk of clinically evident and angiographically documented coronary atherosclerosis and clinical destabilization of coronary plaques, whereas the GLY908ARG polymorphism demonstrated a protective effect on coronary atherogenesis. These correlations were independent of cardiovascular risk factors at multivariable analysis. These findings may contribute to the identification of a novel genetic approach for the stratification of cardiovascular risk profile.     

基质金属蛋白酶9基因-1562C/T多态性与新疆维吾尔族心肌梗死的相关性研究

目的 探讨新疆维吾尔族人群基质金属蛋白酶9(matrix metalloproteinase 9,MMP9)基因启动子区-1562C/T多态性与心肌梗死(myocardialinfarction,MI)发病的相关性.方法 选择经皮冠状动脉造影检查确诊的维吾尔族心肌梗死患者347例(MI组),以同期冠脉造影阴性、排除冠心病诊断的403例维吾尔族患者为对照组.采用聚合酶链反应-限制性片段长度多态性方法对所有纳入对象MMP9基因-1562C/T多态性进行分析,比较两组间MMP9基因多态性频率分布的差异,并结合造影情况,探讨MMP9基因多态性与MI发病及冠脉狭窄程度的关系.结果 MI组CT+TT基因型频率(27.67%)明显高于对照组(14.14%),两组差异具有统计学意义(χ2=20.99,P＜0.01),T等位基因频率在MI组和对照组分别为15.71%、7.56%(χ2=24.57,P＜0.01).Logistic回归分析显示,携带-1562T等位基因的个体发生MI的风险大约升高2倍(OR=2.009,95%CI:1.250～3.230);携带T等位基因合并糖尿病的个体发生MI的风险明显升高(OR=3.714,95%CI:1.299～10.773).MMP9基因-1562C/T多态性分布与MI冠脉狭窄程度差异无统计学意义.结论 MMP9基因-1562C/T多态性可能与新疆维吾尔族人群MI茇病具有相关性;-1562T等位基因可能是MI遗传易感性的基因标记之一;-1562T等位基因与糖尿病在MI发生中具有协同作用.MMP9基因-1562C/T多态性与MI冠脉狭窄程度无关.

Abstract：

Objective To investigate the association between matrix metalloproteinase 9 gene (MMP9)- 1562C/T polymorphism and myocardial infarction (MI) in Uighur population of Xinjiang.Methods A total of 347 patients with MI evidenced by coronary arteriography, and 403 controls free from coronary artery disease with normal angiograms were recruited for the study. Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) was used to detect the -1562C/T functional promoter polymorphism of the MMP9 gene. The relationship between the polymorphism and the severity of coronary arterial stenosis was analyzed. Results The results showed that the frequency of CT and TT genotypes in patients with MI (27. 67%) was significantly higher than that in controls (14. 14%). The frequencies of the - 1562T allele were 15. 71% and 7. 56% in the MI group and the control group respectively (2 = 24.57, P＜0.01). Logistic regression analysis indicated that the T allele carriers (CT+TT) had significantly increased risk of MI compared with the CC carriers (OR=2. 009, 95%CI: 1. 250-3. 230). Individuals carrying the -1562T allele with diabetes mellitus were at an increased risk of MI (OR=3. 714, 95% CI: 1. 299-10. 773). The frequencies of CT and TT genotypes were not significantly different among MI patients with one, two and three or more significantly diseased vessels (χ2 =0. 491, P=0. 782). Conclusion The - 1562C/T polymorphism in the MMP9 gene promoter is associated with the susceptibility to MI in the Uighur population of Xinjiang. The T allele might be a risk factor of MI. And there was a coordinated effect between the -1562T allele and diabetes mellitus in the development of MI.The -1562C/T polymorphism may not be a predictor of the severity of coronary atherosclerosis.     

The --491 TT apolipoprotein E promoter polymorphism is associated with reduced risk for sporadic Alzheimer's disease

Homozygosity for the A allele of the -491 A/T apolipoprotein E (APOE) promoter polymorphism has recently been reported to be associated with sporadic Alzheimer's disease (AD). Two hundred and fifty one patients with AD and an equal number of controls derived from the same region in a Spanish population, were genotyped for -491 A/T and epsilon2/epsilon3/epsilon4 APOE polymorphisms. We did not detect an elevated -491 AA genotype frequency when comparing AD cases to controls. In contrast, persons homozygous for the T allele were at a significantly reduced risk of AD (odds ratio of 0.10, P=0.006). Multiple logistic regression analysis indicated that the -491 TT polymorphism added information on the risk of AD which was independent of that of the APOE epsilon4 allele.     

Relationship between the -374T/A RAGE gene polymorphism and angiographic coronary artery disease

The receptor for advanced glycation end products (RAGE) is thought to play a critical role in diabetic atherosclerosis. Accordingly, a functional -374T/A polymorphism in RAGE gene promoter has been associated with macrovascular complications in type 1 diabetic patients. However, the extent to which this common variant influences the risk of coronary artery disease (CAD) in the general population remains to be determined. We genotyped the -374T/A RAGE polymorphism in 259 non-diabetic individuals, of whom 175 had angiographically documented coronary artery disease (CAD patients) and 84 had normal coronary angiography (CAD-free control subjects). Homozygosity for the -374A allele was found in 9.7% of the CAD patients versus 22.6% of the CAD-free subjects (p=0.005). By means of a multiple logistic regression analysis, the AA genotype of the -374T/A polymorphism was shown to be independently associated with a reduced risk of CAD (adjusted odds ratio 0.33, 95% CI 0.15 to 0.73; p=0.006). Our observations suggest that the -374T/A polymorphism of the RAGE gene may reduce susceptibility to CAD, thus exerting a protective effect on coronary risk. Future pathophysiological studies may be worthwhile to clarify the mechanisms behind this association.