Endothelial nitric oxide (eNOS) gene G894T and VNTR polymorphisms are closely associated with the risk of ischemic stroke development for Asians: meta-analysis of epidemiological studies

Although the relationships between endothelial nitric oxide synthase (eNOS) gene polymorphisms (including G894T, VNTR and T786C) and risk of ischemic stroke (IS) have been extensively studied, controversial results have been reported. The aim of this study was to assess the relationships between them by using a meta-analysis. Literatures were retrieved through the following databases: Medline, Embase and Wangfang (updated to January 1st, 2013). Fixed- or random-effects model was used to calculate pooled odds ratio and 95 % confidence interval (OR and 95 % CI). A total of 31 case–control studies including 8,547 patients and 9,117 controls were included in this meta-analysis eventually. For eNOS G894T polymorphism, the results indicated that TT genotype was significantly associated with increased risk of IS incidence compared to G allele (OR and 95 % CI 1.25 (1.09–1.42) for TT vs. GT+GG, P < 0.001). When subgroup analysis was conducted according to ethnicities, T allele was significantly associated with risk of IS for Asians rather than for Caucasians. For eNOS VNTR polymorphism, 4aa genotype was significantly associated with risk of IS incidence compared to 4bb genotype (OR (95 % CI) 2.22 (1.66–2.97) for aa vs. bb, P < 0.001). Similarly, when subgroup analyses were conducted, 4aa was closely associated with increased risk of IS for Asians rather than for Caucasians. For eNOS T786C polymorphism, it was not associated with risk of IS incidence. In conclusion, this study indicated that eNOS 894T and VNTR 4a allele was significantly associated with risk of IS incidence for Asians. However, eNOS T786C polymorphism was not a likely risk factor for IS incidence.     

Endothelial nitric oxide synthase gene polymorphisms (G894T, 4b/a and T-786C) and preeclampsia: meta-analysis of 18 case-control studies

Studies investigating the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and preeclampsia reported contradictory or nonconclusive results. We performed a meta-analysis of 18 genetic association studies that examined the relationship between preeclampsia and the G894T, 4a/b and T-786C polymorphisms of the eNOS gene. Subgroup analysis by ethnicity and potential sources of heterogeneity and bias were explored. The MEDLINE, EMBASE, and Google Scholar databases were searched to access the relevant genetic association studies up to June 2011. For the allelic analysis of the G894T variant, all studies showed no significant association. For the genotypic analysis, the combined studies of the G allele showed negative significance (odds ratio [OR]=0.56; 95% confidence interval [CI]: 0.33-0.97), all the studies showed positively significance when the T allele was combined (OR=1.17; 95% CI: 1.01-1.36), and results were also positively significant in non-Asian populations (OR=1.20; 95% CI: 1.02-1.43). For the allelic analysis of the 4b/a variant, all studies showed no significant association, but results were negatively significant in non-Asian populations (OR=0.67; 95% CI: 0.46-0.98). For the genotype analysis, combined studies of the b allele showed negative significance (OR=0.55; 95% CI: 0.36-0.84). Moreover, non-Asian studies showed negatively significant results (OR=0.45; 95% CI: 0.28-0.72). For the analysis of the T-786C variant, none of the studies showed significant results. The synthesis of available evidence supports the fact that intron 4a allele, homozygosity for the 894T and intron 4a of eNOS are positively associated with preeclampsia. Large, multiethnic confirmatory, and well-designed studies are needed to determine the relation between preeclampsia and polymorphisms of the eNOS gene.     

Endothelial nitric oxide synthase gene haplotypes and diabetic nephropathy among Asian Indians

Endothelial dysfunction plays a key role in the pathogenesis of diabetic vascular disease, including diabetic nephropathy. Endothelial-derived nitric oxide synthase (eNOS) gene polymorphisms affect eNOS activity and are associated with endothelial dysfunction. We evaluated the association of the constitutive endothelial nitric oxide synthase gene (eNOS) polymorphisms with type 2 diabetic nephropathy. We genotyped three polymorphisms of eNOS (Two SNPs: -786T > C, 894G > T and one 27-bp repeat polymorphism in Intron 4 (27VNTR)) in type 2 diabetic nephropathy patients (cases: n = 195) and type 2 diabetic without nephropathy (controls: n = 255), using validated PCR-RFLP assays. We measured serum NO levels in these subjects and examined its correlation with diabetic nephropathy and eNOS genotypes. The frequency of CC (-786T > C), TT (894G > T) and aa genotypes (27VNTR) were significantly higher in diabetic nephropathy patients as compared to the diabetes without nephropathy group (CC: P = 0.003, TT: P = 0.03, aa: P < 0.0001). These mutant genotypes were found to be associated with higher risk of nephropathy (-786T > C: OR: 5.5, 95%CI: 1.53-19.79; 894G > T: OR: 1.8, 95%CI: 1.03-3.16; Intron 4: OR: 6.23, 95%CI: 2.23-16.31). Haplotype with all the wild alleles (T-b-G) was found to be associated with a decreased risk of nephropathy (OR: 0.68, P = 0.005) and haplotype with all mutant alleles (C-a-T) was associated with higher risk of diabetic nephropathy as compared to diabetes without nephropathy group (OR: 2.6, P = 0.14). No significant linkage disequilibria were observed among the variants in this case-control study. The serum NO levels were observed to be significantly (P < 0.05) lower in mutant allele carriers ('C' allele of T-786C SNP and/or 'T' allele of G894T SNP) as compared with the wild-type allele carriers (-786T and/or 894G) within each of the subject groups (with and without nephropathy). These results suggest that the eNOS gene locus is associated with diabetic nephropathy and the functional polymorphisms (-786T > C & 894G > T) might lead to a decreased expression of eNOS gene.     

Endothelial nitric oxide synthase gene polymorphisms and cardiovascular damage in hypertensive subjects: an Italian case-control study

Background

Nitric oxide (NO) synthesized by endothelial nitric oxide synthase (eNOS) plays an important role in regulation of endothelial function and in the control of blood pressure. However, the results from some studies on the association between three clinically relevant eNOS gene polymorphisms (G894T, T786C and intron 4b/a) and essential hypertension are unclear. We designed a case-control study to evaluate the influence of eNOS polymorphisms on target organ damage in 127 hypertensives and 67 normotensives. Clinical evaluation, biochemical parameters, Urinary Albumin Excretion (UAE) and echocardiogram were performed to characterize target organ damage. eNOS polymorphism were recognized by PCR method.

Results

The distribution of eNOS genotypes was similar in hypertensives and normotensives but 4aa was present in the 2.5% of hypertensives and completely absent in normotensives. Subjects with 4bb, G894T, and T786C genotypes showed an increased prevalence of target organ damage. Moreover prevalence of G894T and introne 4 variants was significantly higher in hypertensives than in normotensives both with cardiovascular damage. Logistic regression analysis didn't show any association between eNOS polymorphisms, Body Mass Index (BMI), hypertension, gender and cardiovascular damage. Only the age (OR 1.11; IC 95% 1.06–1.18) was predictive of cardiovascular damage in our population.

Conclusion

Our results seem to indicate a lack of association with eNOS variants and cardiovascular damage onset.     

The role of endothelial nitric oxide synthase (eNOS) T‐786C,G894T,and 4a/b gene polymorphisms in the risk of idiopathic male infertility

A considerable number of infertile men have no known mechanism for their infertility. This study aims to examine if there is an association between endothelial nitric oxide synthase (eNOS) T‐786C, G894T, and 4a/b gene polymorphisms and idiopathic male infertility. Three hundred fifty‐two men with idiopathic infertility (mean age 32.4 ± 11.4 years) and 356 healthy controls (mean age 33.2 ± 11.6 years) with documented fertility were recruited in this study. Genotypes for T‐786C, G894T, and 4a/b gene polymorphisms were identified by the polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) analysis. The eNOS ?786CC genotype (0.310 vs. 0.081; odds ratio (OR), 3.64; 95% confidence interval (CI), 2.28–4.46; P = 0.001), 894TT genotype (0.131 vs. 0.006; OR, 3.62; 95% CI, 2.68–4.87; P = 0.001) and 4aa genotype (0.128 vs. 0.009; OR, 2.82; 95% CI, 1.88–3.89; P = 0.004) were significantly more frequent in infertile subjects. Furthermore, there was a significant difference between the group of infertile patients with azoospermia and oligoasthenoteratozoospermia (OAT) when compared by genotype distribution (?786CC vs. 786TT, 894TT vs. 894GG, and 4aa vs. 4bb) (all P < 0.01). We also found an association between the eNOS “?786C,” “894T,” and “a” alleles and an increased risk of poor semen parameters. Our data revealed a significant relationship between eNOS genotypes and the phenotype of infertility. Mol. Reprod. Dev. 77: 720–727, 2010. © 2010 Wiley‐Liss, Inc.     

GL261 glioma tumor cells respond to ATP with an intracellular calcium rise and glutamate release

Necrotizing enterocolitis (NEC) is one of the most severe and unpredictable complications of prematurity. There are two possible mechanisms involved in the pathogenesis of NEC: individual inflammatory response and impaired blood flow in mesenteric vessels with secondary ischemia of the intestine. The aim of this study was to evaluate the possible relationship between polymorphisms: Il-1β 3953C>T, Il-6 ?174G>C and ?596G>A, TNFα ?308G>A, and 86 bp variable number tandem repeat polymorphism of interleukin-1 receptor antagonist (Il-1RN VNTR 86 bp) and three polymorphisms that may participate in arteries tension regulation and in consequence in intestine blood flow impairment: eNOS (894G>T and ?786T>C) and END-1 (5665G>T) and NEC in 100 infants born from singleton pregnancy, before 32 + 0 weeks of gestation, exposed to antenatal steroids therapy, and without congenital abnormalities. In study population, 22 (22%) newborns developed NEC. Surgery-requiring NEC was present in 7 children. Statistical analysis showed 20-fold higher prevalence of NEC in infants with the genotype TT [OR 20 (3.71–208.7); p = 0.0004] of eNOS 894G>T gene polymorphism. There was a higher prevalence of allele C carriers of eNOS 786T>C in patients with surgery-requiring NEC [OR 4.881 (1.33–21.99); p = 0.013]. Our investigation did not confirm any significant prevalence for NEC development in another studied genotypes/alleles. This study confirms the significant role of polymorphisms that play role in intestine blood flow. Identifying gene variants that increase the risk for NEC development may be useful in screening infants with inherent vulnerability and creating strategies for individualized care.     

Risk Factors for Normal and High-Tension Glaucoma in Poland in Connection with Polymorphisms of the Endothelial Nitric Oxide Synthase Gene

Aim

The purpose of this study was to evaluate the influence of polymorphisms of the eNOS gene on the clinical status of patients with normal and high tension glaucoma.

Methods

266 Polish Caucasian patients with primary open angle glaucoma were studied. Of the 266, 156 had normal tension glaucoma (NTG) and 110 high tension glaucoma (HTG). DNA material was isolated from peripheral venous blood using commercial kits. Real-time PCR reaction was used to amplify the promoter site of the endothelial nitric oxide synthase (eNOS) gene, including the single nucleotide polymorphism (SNP) site T-786C and part of the 7^th exon of eNOS, including G894T SNP. Genotypes were determined with TaqMan SNP Genotyping Assays.

Results

There were no significant differences in frequencies of the allelic variants of both polymorphisms. In G894T SNP, however, the wild GG form was more common in the HTG group. The SNP of the eNOS gene did not significantly influence the progression rate in either of the groups studied. There were no differences in variants of the eNOS gene regarding the necessity for and success of surgery and the progression of the disease. In the NTG group, no statistical correlation was observed between G894T, T786C polymorphism variants, and risk factors such as optic disc haemorrhages, optic disc notches, and peripapillary atrophy. Mean diastolic and systolic pressure during the day and night were lowest in NTG patients with the CC variant of the T786C polymorphism. No statistical correlation was observed between the G894T and T786C polymorphisms and capillaroscopic examination results.

Conclusions

Genotype frequencies are similar for both the eNOS G894T and T-786C polymorphisms in NTG and HTG patients. These polymorphisms do not correlate with risk factors and do not influence the state of the capillary system in NTG patients. Systolic blood pressure is lower in NTG patients with mutated alleles of both polymorphisms.     

Endothelial Nitric Oxide Synthase (eNOS) gene polymorphisms in spontaneously aborted embryos

Endothelium-derived nitric oxide (NO) is synthesized from L-arginine by endothelial nitric oxide synthase (eNOS) encoded by the eNOS gene on chromosome 7. The effects of the eNOS polymorphisms with the risk of spontaneous pregnancy losses are conflicting. In this study, we investigated the association of the eNOS genotypes with spontaneously aborted embryos in Koreans. Case-control studies were performed to evaluate the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and spontaneously aborted embryos. Ninety-nine spontaneously aborted fetuses at <20 weeks of gestational age and 103 child controls and 282 adult controls. Genotype frequency of three eNOS gene polymorphisms, ?786T>C, VNTR in intron 4 (4a4b), and 894G>T in spontaneously aborted embryos was surveyed. The frequencies of ?786TC and CC genotypes in aborted embryos were significantly higher than in both child and adult controls. The frequencies of 4a4a homozygote of VNTR polymorphism in intron 4 and TT homozygote of 894G>T polymorphisms were also higher in aborted embryos than in adult controls. Haploptype analysis suggested that ?786T>C polymorphism was a possible risk factor for spontaneously aborted embryos. eNOS gene polymorphisms, ?786T>C, VNTR in intron 4 (4a4b), and 894G>T, are associated with the risk of spontaneously aborted fetuses.     

Genetic association studies of endothelial nitric oxide synthase gene polymorphisms in women with unexplained recurrent pregnancy loss: a systematic and meta-analysis

Recurrent pregnancy loss (RPL) is a multifactorial disorder, both genetic and environmental factors contribute to the development of RPL. Recently, the association between endothelial nitric oxide synthase (eNOS) gene polymorphisms and unexplained recurrent pregnancy loss (URPL) has been reported, and the results were inconsistent. Hence, we performed the meta-analysis to drive a more precise estimation of association between eNOS polymorphisms and URPL. Odds ratio (OR) and its 95 % confidence interval were calculated under co-dominant (AA vs. BB, TT vs. GG) and additive (A vs. B, T vs. G) genetic models. Studies of eNOS intron 4 VNTR and Glu298Asp were separated by ethnicities. 13 studies included 1,769 URPL cases and 1,376 healthy controls on eNOS intron 4 VNTR polymorphism, and 11 studies were involved in Glu298Asp polymorphism with 1,498 URPL cases and 1,123 healthy controls. The integrated results showed that eNOS Glu298Asp polymorphism was associated with URPL [ORs were 1.91 (1.42–2.56), P < 0.001; 1.67 (1.36–2.04), P < 0.001, respectively]. When analyses were separated by ethnic subgroups, the association between eNOS Glu298Asp polymorphism and URPL was only observed in East Asians [OR = 1.88 (1.52–2.33), P < 0.001 under additive model], and there was no association between eNOS intron 4 VNTR polymorphism and URPL in Caucasians and East Asians. The results indicated a significant association between eNOS Glu298Asp polymorphism and URPL in East Asians. No association was observed between eNOS intron 4 VNTR polymorphism and URPL in Caucasians and East Asians.     

Genetic polymorphisms of <Emphasis Type="Italic">T-1131C APOA5</Emphasis> and <Emphasis Type="Italic">ALOX5AP SG13S114</Emphasis> with the susceptibility of ischaemic stroke in Morocco

Ischaemic stroke is a multifactorial disease. Genetic polymorphisms involved in lipid, inflammatory and thrombotic metabolisms play an important role in the development of ischaemic stroke. The present study aimed to assess the relationship between T1131C APOA5 and SG13S114 ALOX5AP polymorphisms and the risk of ischemic stroke in 175 cases and 201 controls. Genotyping was performed by high resolution melting and polymerase chain reaction restriction fragment length polymorphism methods. In the case of T-1131C APOA5, a modest risk of ischaemic stroke was noticed with CC (OR: 2.86; 95% CI = 1.24–6.58; Pc = 0.039) and C allele (OR: 1.54; 95% CI = 1.01–2.33; Pc = 0.014). For SG13S114ALOX5AP, a significant association was observed among subjects with TT (OR: 2.57; 95% CI =1.49–4.83; Pc = 0.009) and T allele (OR: 1.59; 95% CI = 1.16–2.19; Pc = 0.008). According to the risk factors of ischaemic stroke, a positive correlation was observed only between SG13S114 variant of ALOX5AP gene and hypertension (Pc = 0.026). Despite lower sample size, T-1131C APOA5 and SG13S114 variants could be considered an independent genetic risk factor of ischaemic stroke in Moroccan population.     

Haplotypes of NOS3 Gene Polymorphisms in Dilated Cardiomyopathy

Dilated Cardiomyopathy (DCM) is characterized by systolic dysfunction, followed by heart failure necessitating cardiac transplantation. The genetic basis is well established by the identification of mutations in sarcomere and cytoskeleton gene/s. Modifier genes and environmental factors are also considered to play a significant role in the variable expression of the disease, hence various mechanisms are implicated and one such mechanism is oxidative stress. Nitric Oxide (NO), a primary physiological transmitter derived from endothelium seems to play a composite role with diverse anti-atherogenic effects as vasodilator. Three functional polymorphisms of endothelial nitric oxide synthase (NOS3) gene viz., T-786C of the 5′ flanking region, 27bp VNTR in intron4 and G894T of exon 7 were genotyped to identify their role in DCM. A total of 115 DCM samples and 454 controls were included. Genotyping was carried out by PCR -RFLP method. Allelic and genotypic frequencies were computed in both control & patient groups and appropriate statistical tests were employed. A significant association of TC genotype (T-786C) with an odds ratio of 1.74, (95% CI 1.14 - 2.67, p = 0.01) was observed in DCM. Likewise the GT genotypic frequency of G894T polymorphism was found to be statistically significant (OR 2.10, 95% CI 1.34–3.27, p = 0.0011), with the recessive allele T being significantly associated with DCM (OR 1.64, 95% CI 1.18 - 2.30, p = 0.003). The haplotype carrying the recessive alleles of G894T and T-786C, C4bT was found to exhibit 7 folds increased risk for DCM compared to the controls. Hence C4bT haplotype could be the risk haplotype for DCM. Our findings suggest the possible implication of NOS3 gene in the disease phenotype, wherein NOS3 may be synergistically functioning in DCM associated heart failure via the excessive production of NO in cardiomyocytes resulting in decreased myocardial contractility and systolic dysfunction, a common feature of DCM phenotype.     

The pathogenetic importance of C774T single nucleotide polymorphism of the endothelial nitric oxide synthase gene in the development of metabolic syndrome

The relationship between nitric oxide production and metabolic disorders and the role of endothelial nitric oxide synthase (eNOS or NOS3) in metabolic syndrome (MS) remain poorly understood and need deeper investigation. In this context the role of the NOS3 gene in pathogenesis of MS is of special interest. The aim of the study was to investigate association of NOS3 single nucleotide polymorphism C774T with risk of MS in the Slavic population of the Kaliningrad region and the relationship of this polymorphic variant with some parameters of endothelial dysfunction. The study included 128 patients (48 men and 80 women aged from 36 to 52 years) with MS. The control group consisted of 126 healthy volunteers (60 men and 66 women aged from 30 to 40 years). Genotyping was performed by real-time PCR. Serum nitrite levels were determined spectrophotometrically by the Griess method. Serum levels of endothelin-1 and eNOS were evaluated by ELISA. The study has shown association of T allele (OR = 2.06; p = 0.0004; CI: 1.38–3.08) and CT genotype (OR = 1.97; p = 0.014; CI: 1.14–3.40 ) C774T polymorphism of the NOS3 gene with risk of MS in the Slavic population of the Kaliningrad region. Allele C (OR = 0.48; p = 0.0004; CI: 0.32–0.72) and homozygous CC genotype (OR = 0.41; p = 0.001; CI: 0.24–0.69) C774T polymorphism of the NOS3 gene were associated with reduced risk of the development of MS. Significant differences in serum levels of eNOS and endothelin-1 depended on the CT and TT genotypes of C774T polymorphism of the NOS3 gene in MS.     

An updated meta-analysis of endothelial nitric oxide synthase gene: three well-characterized polymorphisms with hypertension

Background

Numerous individually underpowered association studies have been conducted on endothelial nitric oxide synthase (eNOS) genetic variants across different ethnic populations, however, the results are often irreproducible. We therefore aimed to meta-analyze three eNOS widely-evaluated polymorphisms, G894T (rs1799983) in exon 7, 4b/a in intron 4, and T−786C (rs2070744) in promoter region, in association with hypertension from both English and Chinese publications, while addressing between-study heterogeneity and publication bias.

Methods

Data were analyzed using Stata software (version 11.0), and random-effects model was applied irrespective of between-study heterogeneity, which was evaluated by subgroup and meta-regression analyses. Publication bias was weighed using the Egger''s test and funnel plot.

Results

There were total 19284/26003 cases/controls for G894T, and 6890/6858 for 4b/a, and 5346/6392 for T−786C polymorphism. Overall comparison of allele 894T with 894G in all study populations yielded a 16% increased risk for hypertension (odds ratio [OR] = 1.16; 95% confidence interval [95% CI]: 1.07–1.27; P = 0.001), and particularly a 32% increased risk (95% CI: 1.16–1.52; P<0.0005) in Asians and a 40% increased risk (95% CI: 1.19–1.65; P<0.0005) in Chinese. Further subgroup analyses suggested that published languages accounted for the heterogeneity for G894T polymorphism. The overall OR of allele 4a versus 4b was 1.29 (95% CI: 1.13–1.46; P<0.0005) in all study populations, and this estimate was potentiated in Asians (OR = 1.42; 95% CI: 1.16–1.72; P<0.0005). For T−786C, ethnicity-stratified analyses suggested a significantly increased risk for −786C allele (OR = 1.25; 95% CI: 1.06–1.47; P = 0.007) and −786CC genotype (OR = 1.69; 95% CI: 1.20–2.38; P = 0.003) in Whites. As an aside, the aforementioned risk estimates reached significance after Bonferroni correction. Finally, meta-regression analysis on other study-level covariates failed to provide any significance for all polymorphisms.

Conclusion

We, via a comprehensive meta-analysis, ascertained the role of eNOS G894T and 4b/a polymorphisms on hypertension in Asians, and T−786C polymorphism in Whites.     

Association between <Emphasis Type="Italic">TNF,IL1B,IL6, IL10</Emphasis> and <Emphasis Type="Italic">IFNG</Emphasis> polymorphisms and recurrent miscarriage: a case control study

Background

Approximately half of recurrent miscarriages have unexplained etiology. Recent evidences suggest that cytokines are important determinants in pregnancy maintenance and as such, cytokine gene polymorphisms, which can affect cytokine production and/or functionality, could play a role in the disorder. Thus, we aimed to investigate the association of selected cytokine gene polymorphisms with risk of recurrent miscarriage among Chinese.

Methods

TNF -238G > A, TNF -308G > A, IL1B -511 T > C, IL1B 3954C > T, IL6 -174G > C, IL6 -634C > G, IL10 -1082A > G and IFNG 874A > T polymorphisms were genotyped on 775 women with idiopathic recurrent miscarriage and 805 healthy parous control women. Logistic regression analysis was performed to determine the odds ratios (ORs) of the association between the polymorphisms and recurrent miscarriage risk.

Results

Among the eight polymorphisms studied, only the IL1B -511 T > C and IL6 -634C > G polymorphisms showed statistically significant associations with recurrent miscarriage risk. For the former, a significantly increased risk of recurrent miscarriage was observed for the mutant (CC) genotype (OR: 1.377; 95% CI: 1.039–1.824; P?=?0.026). However, for the IL6 -634C?>?G polymorphism, a decreased recurrent miscarriage risk was observed for the heterozygous (CG) genotype (OR: 0.614; 95% CI: 0.493–0.765; P < 0.001) and the mutant (GG) genotype (OR: 0.414; 95% CI: 0.251–0.684; P?=?0.001).

Conclusions

The IL1B -511 T > C polymorphism may serve as important risk factor for recurrent miscarriage while the IL6 -634C > G polymorphism may protect against the risk of recurrent miscarriage.

     

Association of eNOS gene polymorphisms with essential hypertension in the Han population in southwestern China

Endothelial nitric oxide synthase (eNOS) plays an important role in maintaining blood pressure homeostasis and vascular integrity. Polymorphisms in the eNOS gene have been found to be associated with hypertension in different human populations, including Northern and Southern Chinese Han populations. To examine the relationship of three eNOS gene polymorphisms, T-786C (rs2070744), G894T (rs1799983), and G10T (rs7830), with hypertension in the Han population in southwestern China, we carried out a study of the genotypes of three SNPs in 510 hypertensive and 510 normotensive subjects from the Yunnan Province by using PCR-RFLP and sequencing. Our SNP analyses showed that the distribution of the T-786C polymorphism did not differ between patients and controls, and that G894T and G10T are significantly associated with hypertension in females, adjusted for covariates. Compared with the other haplotypes, haplotype H1 (TGG), carrying protective 10G and 894G alleles, significantly decreased the risk of increased essential hypertension in females, with an odds ratio of 0.68 (P = 10(-5)). These results suggest that the eNOS polymorphism is one of the factors contributing to the predisposition for essential hypertension in the Han population in southwestern China.     

Association of polymorphisms of endothelial nitric oxide synthase (eNOS) gene with the risk of primary open angle glaucoma in a Brazilian population

The present study aimed to investigate the association of endothelial nitric oxide synthase (eNOS) gene polymorphisms with primary open angle glaucoma (POAG). We conducted a case-control study that included 90 patients with POAG and 127 healthy controls whose blood samples were genotyped for the functional polymorphisms T-786C and Glu298Asp of the eNOS gene by Taqman fluorescent allelic discrimination assay. The T-786C polymorphism was significantly associated as a risk factor for POAG among women (OR: 2.28; 95% CI: 1.11 to 4.70, p=0.024) and marginally associated to the risk of POAG in the patients ≥52 years of age at diagnosis (OR: 2.11; 95% CI: 0.98 to 4.55, p=0,055). However, these results was not confirmed after adjustments for gender, age, self-declared skin color, tobacco smoking and eNOS genotypes by multivariate logistic regression model (OR: 2.08; 95% CI: 0.87 to 5.01, p=0.101 and OR: 2.20; 95% CI: 0.95 to 5.12, p=0.067, respectively). The haplotype CG of T-786C and Glu298Asp showed a borderline association with risk of POAG in the overall analysis (OR: 1.76; 95% CI: 0.98 to 3.14, p=0.055) and among women (OR: 2.02; 95% CI: 0.98 to 4.16, p=0.052). Furthermore, the CG haplotype was significantly associated with the development of POAG for the age at diagnosis group ≥52 years (OR: 3.48; 95% CI: 1.54 to 7.84, p=0.002).We suggested that haplotypes of the polymorphisms T-786C and Glu298Asp of eNOS may interact with gender and age in modulating the risk of POAG.     

Oxidative Stress-Related Genes in Type 2 Diabetes: Association Analysis and Their Clinical Impact

Worldwide prevalence of diabetes mellitus motivates a number of association studies to be conducted throughout the world. Eleven polymorphisms from nine candidate genes in oxidative stress pathway have been analyzed in eastern Indian type 2 diabetic patients (n = 145) and healthy controls (n = 100). Different biochemical parameters were also analyzed for their association with the disease. Significant associations were observed for rs2070424 A>G SOD1 (OR 3.91, 95% CI 2.265–8.142, P < 0.001), rs854573 A>G PON1 (OR 3.415, 95% CI 2.116–5.512, P < 0.001), rs6954345 G>C PON2 (OR 3.208, 95% CI 2.071–4.969, P < 0.001), RAGE rs1800624 ?374 T>A (OR 3.58, 95% CI 2.218–5.766, P < 0.001), and NOS3 ?786 T>C (OR 3.75, 95% CI 2.225–6.666, P < 0.001). Haplotype containing two risk alleles of PON1 and PON2 genes was significantly associated with disease (OR 8.34, 95% CI 1.554–44.804, P < 0.002). Our results suggest that carriers of major and efficient alleles of oxidative stress genes are more likely to survive the comorbid complications and single copy of risk allele is sufficient for developing the disease.     

The T-786C and C774T endothelial nitric oxide synthase gene polymorphisms independently affect the onset pattern of severe diabetic retinopathy.

Genetic factors could be implicated in the pathogenesis of severe diabetic retinopathy (DR). Recently, we reported a strong association between the eNOS4b/a endothelial nitric oxide synthase (eNOS) polymorphism and severe DR. To examine whether T-786C and C774T eNOS polymorphisms are involved in severe DR, 254 Caucasians with longstanding C-peptide-negative type 1 diabetes, 128 patients with absent/mild DR (control group), and 126 patients with preproliferative/proliferative DR (study group) were genotyped. The distribution of T-786C and C774T eNOS polymorphisms was in Hardy-Weinberg equilibrium and did not differ between the study and control groups. However, in case patients (n=126), T-786C and C774T polymorphisms influenced the onset pattern of severe DR (P=0.0169 and P=0.0257, respectively). The C-786C genotype was associated with early-onset severe DR (duration of diabetes: 15.2+/-5.9 vs. 19.4+/-6.3 years, P=0.0105), and the homozygous T774T genotype was associated with late-onset severe DR (24.3+/-7.0 vs. 18.4+/-6.2 years, P=0.0067). In the case of patients with high glycosylated hemoglobin levels (HbA1c >8%, n=88), the association between the T-786C polymorphism and early-onset severe DR was stronger (P=0.0068). Case patients carrying the C-786C genotype had higher HbA1c values (9.61+/-1.89%) than those carrying the T-786T genotype (8.93+/-1.47%, P=0.0173). Multivariate analysis showed that T-786C polymorphism was the best independent factor for onset pattern of severe DR (P<0.001). These findings, supported by previous associations between eNOS4b/a polymorphism and DR, suggest that T-786C and C774T eNOS polymorphisms affect the onset pattern of severe DR.     

Polymorphisms in <Emphasis Type="Italic">VEGF-A</Emphasis> are associated with COPD risk in the Chinese population from Hainan province

In this study, we examined and validated how common variants contribute to susceptibility to chronic obstructive pulmonary disease (COPD) in the Han Chinese population. Here, we genotyped 18 nucleotide polymorphisms and evaluated their association with COPD using chi-square test and genetic model analysis (246 COPD patients and 350 controls), and found three SNPs that might cause a predisposition to COPD. Both rs3025030 and rs3025033 are located on chromosome 6 in VEGF-A. We found one risk allele ‘C’ from rs3025030 and another ‘G’ from rs3025033 using the log-additive model (OR 1.40; 95% CI 1.05–5.96; P = 0.022), (OR 1.38; 95% CI 1.03–1.84; P = 0.03). We also found another risk allele ‘A’ of rs9296092 in gene region ZBTB9-BAK1 by the allele model (OR 2.63; 95% CI 1.27–5.45; P = 0.0078), (adjusted OR 3.53; 95% CI 1.12–11.11; P = 0.031). We found a risk haplotype ‘CG’ associated with the risk of COPD (OR 1.39; 95% CI 1.04–1.86; P=0.028). Our results when compared with previous studies showed significant association between VEGF-A polymorphism and COPD. We also identified rs9296092 as a risk factor for COPD.