Tandem Repeat Polymorphism In Intron Research Articles

Erectile dysfunction in cardiovascular patients: A prospective study of the eNOS gene T‐786C, G894T, and INTRON variable number of the tandem repeat functional interaction

AbstractBackgroundCardiovascular disease induces erectile dysfunction modulated by endothelial nitric oxide synthase enzyme and an impaired ejection fraction that restricts penis vascular congestion. However, the mechanisms regulating endothelial dysfunction are not understood.ObjectivesExploring the functional impact of endothelial nitric oxide synthase genetic polymorphisms on erectile dysfunction and drug therapy optimization in high‐risk cardiovascular disease patients.Materials and methodsPatients with erectile dysfunction symptoms and candidates for andrology therapy were included (n = 112). Clinical data and endothelial nitric oxide synthase rs1799983 (G894T) and rs2070744 (T‐786C), genotyped by fluorescence polarization assays, were registered. The 27‐bp variable number of the tandem repeat polymorphism in intron 4 (intron4b/a) was analyzed by polymerase chain reaction‐restriction fragment length polymorphism. Association analyses were run with the R‐3.2.0 software.ResultsA significant association between endothelial nitric oxide synthase 786‐TT (p = 0.005) and the aa/ac of intron 4 variable number of the tandem repeat (p = 0.02) with higher erectile dysfunction susceptibility was observed in cardiovascular disease patients (60 ± 9 years, 66% severe erectile dysfunction, 56% ejection fraction). After 3‐months of phosphodiesterase type 5 inhibitors, erectile dysfunction (International Index of Erectile Function, 50 ± 16 scores, the International Index of Erectile Function‐Erectile Function 21 ± 10 scores, p < 0.001) and sexual quality of life (modified Sexual Life Quality Questionnaire 55 ± 23 scores, p < 0.001) had significantly improved. The cardiovascular ejection fraction was influenced positively with better sexual quality of life (0.1941), and also in the endothelial nitric oxide synthase G894‐T allele (p = 0.076) carriers, which could merit future analyses. Erectile dysfunction was present as the primary clinical manifestation in 62% of cases, with cardiovascular disease occurring concurrently. Only former smokers and obese subjects debuted prior to cardiovascular disease than to erectile dysfunction.ConclusionsOur study provides comprehensive insights into the functional interaction linking endothelial nitric oxide synthase gene polymorphisms, erectile function, and ejection fraction in high‐risk cardiovascular disease patients. Future therapeutic strategies could target endothelial nitric oxide synthase activity by including lifestyle changes and epigenetic modulations.

Endothelial nitric oxide synthase gene intron 4 variable number tandem repeat polymorphism in β-thalassemia major: relation to cardiovascular complications.

Endothelial nitric oxide synthase (eNOS), an enzyme that generates nitric oxide, is a major determinant of endothelial function. Several eNOS gene polymorphisms have been reported as 'susceptibility genes' in various human diseases states, including cardiovascular, pulmonary and renal diseases. We studied the 27-base pair tandem repeat polymorphism in intron 4 of eNOS gene in 60 β-thalassemia major (β-TM) patients compared with 60 healthy controls and assessed its role in subclinical atherosclerosis and vascular complications. Patients were evaluated stressing on transfusion history, splenectomy, thrombotic events, echocardiography and carotid intima-media thickness (CIMT). Analysis of eNOS intron 4 gene polymorphism was performed by PCR. No significant difference was found between β-TM patients and controls with regard to the distribution of eNOS4 alleles or genotypes. The frequency of eNOS4a allele (aa and ab genotypes) was significantly higher in β-TM patients with pulmonary hypertension or cardiomyopathy. Logistic regression analysis revealed that eNOS4a allele was an independent risk factor for pulmonary hypertension in β-TM patients [odds ratio (OR) 2.2, 95% confidence interval (95% CI) 1.19-5.6; P < 0.001]. We suggest that eNOS intron 4 gene polymorphism is related to endothelial dysfunction and subclinical atherosclerosis and could be a possible genetic marker for prediction of increased susceptibility to cardiovascular complications.

Association Between a 27-bp Variable Number of Tandem Repeat Polymorphism in Intron 4 of the eNOS Gene and Risk for Diabetic Retinopathy Type 2 Diabetes Mellitus: A Meta-Analysis

Purpose: Imbalance in the production of endothelial nitric oxide synthase (eNOS), which plays an essential role in retinal vascular function, can lead to the development of diabetic retinopathy (DR). To thoroughly address this issue, we performed an updated meta-analysis to evaluate the association between the eNOS 27VNTR (4b/4a) polymorphism and DR in type 2 diabetes mellitus (T2DM).Methods: A search was conducted of PubMed and Chinese language (WanFang) databases through 3 March 2013. Data were retrieved in a systematic manner and analyzed using Stata Statistical Software. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations.Results: Based on the search criteria for DR susceptibility related to the 27VNTR (4b/4a) polymorphism of the eNOS gene, 16 case-control studies (15 articles), comprising 3227 T2DM patients with DR and 3437 T2DM patients without DR, were retrieved. Although no significant associations were uncovered in either the overall analysis or DR subtype groups, a decreased association was detected between the African- (allelic contrast: OR = 0.75, 95% CI = 0.65–0.88) or population-based (PB) studies (dominant genetic model: OR = 0.91, 95% CI = 0.83–0.98) and the eNOS 27VNTR (4b/4a) polymorphism. Stratification according to average duration of DM revealed that T2DM patients with histories of >10 years had an elevated susceptibility to DR compared with those with histories of shorter durations (homozygote comparison: OR = 1.67, 95% CI = 1.09–2.58).Conclusions: The present meta-analysis suggests that the eNOS 27VNTR (4b/4a) polymorphism potentially decreases the risk of developing DR in T2DM African individuals. The higher degree of susceptibility in patients with longer (>10 years) durations of DM is indicative of the involvement of a gene-environment interaction in determining the risk for DR. Further studies, based on larger sample sizes and additional gene-environment interactions, should be conducted to elucidate the role of eNOS gene polymorphisms, especially 27VNTR (4b/4a), in the risk for DR.

Prediction and structural equation model of sertraline treatment response in Japanese patients with major depressive disorder

The aim of this study was to extract the factors possibly associated with sertraline treatment response and elucidate their interactions and extent of influence. Demographic state, stress state, personality, and eight genetic polymorphisms at baseline and clinical symptoms at baseline and 8 weeks were analyzed and examined by logistic regression and a structural equation model in sertraline treatment study of 96 Japanese patients with major depressive disorder. Non-responders were associated with higher scores of harm avoidance in Temperament and Character Inventory, higher scores (≥24) of 17-item Hamilton Rating Scale for Depression at baseline, recurrence, and 12/12 genotype of the serotonin transporter variable number of tandem repeat polymorphism in intron 2 (5HTTSTin2). When we calculated the response index using four factors extracted, the mean response index value of non-responders was significantly higher than that of responders. The symptoms at baseline, personality, recurrence, and polymorphism of 5HTTSTin2 showed significantly direct and positive influences on the symptoms at 8 weeks in our final structural equation model with a good model fit. Considering the combination of four factors extracted may be useful for predicting a worse response to sertraline treatment and selecting different treatment other than sertraline.

Endothelial nitric oxide synthase VNTR (intron 4 a/b) polymorphism association with nonsyndromic oral clefts

Objective: Nonsyndromic cleft lip with or without cleft palate (NSCLP) is a common birth defect with substantial clinical and social impact, and whose causes include both genetic and environmental factors. Folate and homocysteine metabolism have been indicated to play a role in the etiology of NSCLP. The aim of this study was to determine the prevalence of NOS3 27-bp VNTR and to evaluate whether this polymorphism contributed to the risk of NSCLP. Material and methods: We studied the 27 base pair tandem repeat polymorphism in intron 4 of the endothelial nitric oxide synthase (NOS3) gene in 230 unrelated individuals belong to 7 Indian populations along with 141 NSCLP cases and 142 unrelated controls. The genotyping was performed by polymerase chain reaction and electrophoresis. The data were statistically analysed using the χ2-test. Results: The NOS3 27-bp VNTR 4a allele is present in six of the seven populations analysed and allele frequencies range from 6.8% in Sugali to 23.5% in Madiga populations. NOS3 showed protective association with predisposition towards NSCLP for the heterozygous (4b/a) genotypes (4b/b vs. 4b/a: OR =0.58, 95% CI =0.34 to 0.99, p=0.044). Conclusions: The current study suggests significant differences in the frequency of the NOS3 VNTR allele across the populations. There is protective association between NOS3 27-bp VNTR polymorphism and NSCLP in the Indian population.

Distribution of 42-bp variable tandem repeat polymorphism of the cold-induced autoinflammatory syndrome 1 (CIAS1) gene in eight human populations

We recently identified a 42 bp Variable Number of Tandem Repeats polymorphism in intron 4 of Cold-induced autoinflammatory syndrome 1 gene (CIAS1 42 bp-VNTR), which are associated with CIAS1 gene expression and some inflammatory disease. The aim of our study is to investigate whether variability of CIAS1 42 bp-VNTR allele is difference among races. A total of 1291 subjects from 7 populations (178 Chinese, 95 Korean, 614 Mongolian, 49 Bangladesh, 72 Sri Lanka, 192 African and 91 European) was genotyped on CIAS1 42 bp-VNTR polymorphism, which was also compared to previous genotyping data from 508 Japanese subjects. A total of 11 genotypes and 5 alleles were found in 8 populations. The range of allele frequencies of CIAS1∗6, CIAS1∗7, CIAS1∗9, CIAS1∗12, and CIAS1∗13 were 0.000–0.167, 0.056–0.248, 0.008–0.203, 0.570–0.923, and 0.000–0.104 in eight populations. The CIAS1∗12 was the most common allele among all populations. The longest allele CIAS1∗13 in African population was extremely high frequent at 0.104 compared to other population. While shortest allele CIAS1∗6 was not observed Sri Lankan and African. Frequency (0.924) in the Sri Lankan population. These results showed that the CIAS1 42 bp-VNTR polymorphism could represent genetic diversity among different human populations.

Interleukin-1 receptor antagonist intron 2 variable number of tandem repeats polymorphism and respiratory failure in children with community-acquired pneumonia*

To determine whether the variable nucleotide tandem repeat polymorphism in intron 2 of the interleukin-1 receptor antagonist gene is associated with lung injury in children with community-acquired pneumonia. A prospective cohort of children diagnosed with community-acquired pneumonia. Two pediatric hospitals. Eight hundred fifty pediatric patients with community-acquired pneumonia were enrolled. Genotyping of the variable nucleotide tandem repeat polymorphism in intron 2 of the interleukin-1 receptor antagonist gene was performed on DNA isolated from whole blood. The requirement for positive pressure ventilation or the diagnosis of acute lung injury or acute respiratory distress syndrome were the main outcomes of the study. Children (14 days-19 yrs) with community-acquired pneumonia (850) were enrolled; analysis was limited to African American (515) and Caucasian (232) patients. Of the 82 patients requiring positive pressure ventilation, 44 were diagnosed with acute lung injury or acute respiratory distress syndrome. Multivariate logistic regression analyses indicated that children without a copy of the A1 allele of the variable nucleotide tandem repeat polymorphism in intron 2 of the interleukin-1 receptor antagonist gene were more likely to need positive pressure ventilation compared to those with one or two copies of this allele (odds ratio = 2.65, confidence interval, 1.02-6.90). In addition, the absence of the A1 allele also appeared to be associated with the development of community-acquired pneumonia-induced acute lung injury/acute respiratory distress syndrome (odds ratio = 3.1, confidence interval, 0.99-9.67). In children with community-acquired pneumonia, absence of the A1 allele at the interleukin-1 receptor antagonist intron 2 polymorphic site is associated with increased risk for more severe lung injury, as measured by the need for positive pressure ventilation or the development of acute lung injury or acute respiratory distress syndrome. Conversely, presence of the A1 allele is associated with decreased risk for more severe lung injury in this patient population.

Surfactant protein-B polymorphisms and mortality in the acute respiratory distress syndrome.

To determine whether polymorphisms of the surfactant protein B gene may be associated with increased mortality in patients with the acute respiratory distress syndrome. A prospective cohort study. Four adult intensive care units at a tertiary academic medical center. Two hundred fourteen white patients who had met criteria for acute respiratory distress syndrome. None. Patients were genotyped for a variable nuclear tandem repeat polymorphism in intron 4 of the surfactant protein B gene and the surfactant protein B gene +1580 polymorphism. For the variable nuclear tandem repeat surfactant protein B gene polymorphism, patients were found to have either a homozygous wild-type genotype or a variant genotype consisting of either a heterozygous insertion or deletion polymorphism. Logistic regression was performed to analyze the relationship of the polymorphisms to mortality in patients with acute respiratory distress syndrome. In multivariate analysis, the presence of variable nuclear tandem repeat surfactant protein B gene polymorphism was associated with a 3.51 greater odds of death at 60 days in patients with acute respiratory distress syndrome as compared to those patients with the wild-type genotype (95% confidence interval 1.39-8.88, p = 0.008). There was no association found between the +1580 variant and outcome (p = 0.15). In this study, the variable nuclear tandem repeat surfactant protein B gene polymorphism in intron 4 is associated with an increased 60 day mortality in acute respiratory distress syndrome after adjusting for age, severity of illness, and other potential confounders. Additional studies in other populations are needed to confirm this finding.

Association between obsessive–compulsive disorder and a variable number of tandem repeats polymorphism in intron 2 of the serotonin transporter gene

Background Pharmacological studies indicate a dysregulation of the serotonergic system in obsessive–compulsive disorder (OCD). A variable number tandem repeats (VNTR) polymorphism with three alleles (Stin2.9, Stin2.10, Stin2.12) has been described in intron 2 of the serotonin transporter (5-HTT) gene. This polymorphism has been associated with unipolar depression, bipolar disorder, schizophrenia, and anxiety disorders including OCD. Methods The association between OCD and the polymorphism is examined in 97 OCD patients, 578 psychiatric controls and 406 healthy controls, all Spanish Caucasians. Results Genotype frequencies for the polymorphism were significantly different in OCD patients, psychiatric patients and controls. There was a significant excess of 12/12 and 12/10 genotypes in OCD patients compared to psychiatric patients and controls. Conclusions Our results indicate a possible association between the Stin2.12 allele of the VNTR polymorphism and OCD.

Endothelial Nitric Oxide Synthase Polymorphisms and Susceptibility to Hypertension: Genotype Versus Haplotype Analysis

To the Editor: Zintzaras et al reported interesting results of a meta-analysis of all the available studies on the possible association between endothelial NO synthase ( eNOS ) polymorphisms and hypertension.1 They concluded that there is evidence for significant association between the 4b/4a variable number of tandem repeats polymorphism in intron 4 of the eNOS gene and susceptibility to …

Association of interleukin-1 gene cluster polymorphisms with ischemic stroke in a Chinese population

Chronic inflammatory process plays an important role in atherothrombosis. Interleukin-1 (IL-1) is one of the key modulators of the inflammatory response and its activity is critically regulated by its receptor antagonist (IL-1Ra). A variable number tandem repeat polymorphism in intron 2 of IL-1Ra gene and a C to T single base polymorphism in the promoter of IL-1beta gene (C(-511)-->T) have been reported to affect the levels of IL-1 as well as its antagonist, IL-1Ra. It is also reported in several studies that these polymorphisms are associated with the susceptibility to cardio-cerebral vascular disease. However, data are limited in China. In this article, we studied the relationships between these polymorphisms and the risk of ischemic stroke in China. One hundred and twelve patients committed ischemic stroke were compared with 95 demographically matched healthy volunteers. The frequencies of the IL-1Ra 1/1 genotype and IL-1Ra allele 1 (Ra*1 allele) in stroke patients were significantly higher than those in healthy volunteers [93.7% vs. 82.1%, P =0.014; 0.964 vs. 0.905, P =0.007]. No significant differences were found in the IL-1beta -511 genotype and the allele distribution between the two groups. Our results implicated that IL-1 gene polymorphism might be associated with the susceptibility to ischemic stroke.

Body Mass Index but Not a Polymorphism of the Interleukin-1 Receptor Antagonist (IL-1 RA) Gene Is Associated with Age at Natural Menopause

Background: A genetic component of the onset of menopause has been described and several candidate genes have been identified. We hypothesized that carriage of a polymorphism of the interleukin-1 receptor antagonist gene (IL-1 RA) is associated with an early age at menopause. Methods: In a prospective cohort study, 90 consecutive postmenopausal Caucasian women were genotyped by PCR for the presence of an 86-base pair tandem repeat polymorphism in intron 2 of IL-1 RA. Results: We found that 36/90 (40%) women were homozygous for the wild-type allele 1 and 49/90 (54%) women were heterozygous for any of the variant alleles (1/2 [n = 44], 1/3 [n = 3], 2/3 [n = 2]). Two women (2%) were homozygous carriers of the variant allele 2. The wild-type allele 1 was identified on 119 of 180 chromosomes for an allele frequency of 0.66. The polymorphic alleles 2 and 3 were present on 56 and 5 chromosomes, respectively (allele frequencies 0.31 and 0.03, respectively). No correlation between the IL-1 RA genotype and the age at menarche and menopause, the length of the reproductive period, and the number of deliveries and miscarriages was ascertained. As to allele frequencies, homozygous and heterozygous carriers of the variant allele 2 had a median age at menopause of 50 (range 40–48) years, compared to 49.5 (range 39–56) years for women with no allele 2 (p value 0.41). Women with at least one allele 2 had a median age at menarche of 13 (range 10–16) years, compared to 13 (range 10–17) years for women with no allele 2 (p value 0.1). Decreasing body mass index, but not smoking, was correlated with an increasing age at natural menopause (r = –0.23, p = 0.04). Conclusions: Our preliminary data suggest that an 86-base pair tandem repeat polymorphism in intron 2 of IL-1 RA does not modulate the onset and cessation of menses in this cohort of Caucasian women.

Polymorphisms in Interleukin-1β and Interleukin-1 Receptor Antagonist Genes Are Associated with Kidney Failure in Korean Patients with Type 2 Diabetes mellitus

Background/Aim: Cytokines play an important role in the pathogenesis of kidney diseases. The aim of the study was to investigate the impact of interleukin (IL)-1 cluster genes on diabetic nephropathy in Korean patients with type 2 diabetes mellitus (DM). Methods: We investigated –511 C/T polymorphism of IL-1β and tandem repeat polymorphism in intron 2 of IL-1 receptor antagonist in type 2 DM patients with end-stage kidney failure as compared with patients without nephropathy. Results: The IL1B2 allele was found more frequently in patients with kidney failure than in controls (57.4 vs. 46.1%, p < 0.05). An excessive homozygous carriage of IL1B2 was found in patients with kidney failure when compared with controls (30.5 vs. 18.3%, p < 0.05). The allelic frequency of IL1RN*2 was also higher in cases than in controls without nephropathy (8.4 vs. 2.8 %, p < 0.05). The carriage rate of IL1RN*2 was significantly associated with an increased risk of kidney failure (15.8 vs. 5.6%; OR 3.19, 95% CI 1.24–8.17). The risk of kidney failure was highest in those carrying both IL1RN*2 and IL1B2 (OR 3.90, 95% CI 1.34–11.40). Conclusion: IL1B2 and IL1RN*2 genotypes of the IL-1 cluster genes are associated with diabetic nephropathy in Korean patients with type 2 DM.

Association Study of Serotonin Transporter Gene VNTR Polymorphism and Mood Disorders, Onset Age and Suicide Attempts in a Chinese Sample

The human serotonin transporter (5-HTT) gene is an important candidate for the pathogenesis of mood disorders. Associations have been reported between a variable-number tandem-repeat polymorphism in intron 2 of the serotonin transporter gene (5-HTTVNTR) and mood disorders in a number of studies of Western and Chinese populations. However, no such relationships have been determined in other analogous research. To replicate these positive findings in a Chinese population and to determine the association between onset age of bipolar disorder and 5-HTTVNTR, we investigated the prevalence of this polymorphism in an independent Chinese population (83 bipolar disorder patients, 77 major depressive disorder patients and 169 controls), demonstrating no significant association between the 5-HTTVNTR polymorphism and mood disorders or age at onset. Further, no association was demonstrated between this polymorphism and suicidal history in mood disorder patients. These negative findings suggest that 5-HTTVNTR does not play a major role in the pathogenesis of mood disorder in Chinese populations.

Interleukin-1 cluster combined genotype and restenosis after balloon angioplasty.

The interleukin-1 system is fundamentally involved in the pathogenesis of restenosis after percutaneous transluminal angioplasty (PTA). In order to further define the clinical impact of genetic variation in this potent proinflammatory pathway we investigated the joint effects of two single nucleotide polymorphisms in the interleukin-1 beta gene [IL-1B(-511) and IL-1B(+3954)] and a variable number tandem repeat polymorphism in intron 2 of the interleukin 1 receptor antagonist gene (IL-1RN VNTR) on postintervention inflammation and occurrence of restenosis in 183 consecutive patients who underwent successful femoropopliteal PTA. C-reactive protein (CRP) and serum amyloid A (SAA) were determined pre- and 48 hours postintervention. Patients were followed up to 12 months for the occurrence of postangioplasty restenosis (> or = 50%). When analyzed separately, none of the polymorphisms was associated either with inflammation or restenosis. However, when the IL-1B (-511) and the IL-1RN VNTR genotypes were combined, a highly significant relationship was observed: Non-carriers of the two repeat allele of the IL-1RN VNTR (IL-1RN*2) who were heterozygous and homozygous for the IL-1B (-511)T allele exhibited a gradually increased inflammatory response and a higher restenosis risk. In contrast, carriers of the IL-1RN*2 and the IL-1B (-511)T allele showed a significantly better outcome. This remarkable gene dose-dependent association emphasizes the advantage of considering combinations of genetic markers rather that isolated polymorphisms in the analysis of multifactorial vascular disease.

A polymorphism of the Nos3 gene and age at natural menopause

Objective To investigate the possible influence of a polymorphism of the Nos3 gene on menarche and onset of menopause in humans. Design Cohort study. Setting Academic research institution. Patient(s) Ninety-one consecutive Caucasian postmenopausal women. Intervention(s) Peripheral venous puncture and a patient questionnaire were administered. Main outcome measure(s) A tandem repeat polymorphism in intron 4 of Nos3 was analyzed by polymerase chain reaction amplification. Result(s) The common B allele was identified on 143 of 182 chromosomes (frequency 0.79). The polymorphic A allele was present on 39 chromosomes (frequency 0.21). The genotype frequencies were as follows: 58.2% (B/B), 40.7% (A/B), and 1.1% (A/A). Age at menarche, number of deliveries, number of miscarriages, and onset of menopause did not differ between genotypes. Smoking and increased body mass index were associated with an earlier onset of natural menopause. Conclusion(s) In contrast to mouse models, in humans Nos3 does not seem to modulate onset and cessation of menses.

Serotonin transporter genetic polymorphisms and harm avoidance in the Chinese

The association for the harm avoidance (HA) dimension, as assessed by the Tridimensional Personality Questionnaire (TPQ), and the serotonin-transporter genetic polymorphisms has been investigated with controversial results. The aim of the present study was to replicate this investigation and to establish the association for a Chinese population. Two polymorphisms of the serotonin transporter (5HTT-LPR, serotonin transporter-linked polymorphism region; 5HTT-VNTR, variable number tandem repeat polymorphism in intron 2 of the serotonin transporter gene) were determined for 192 healthy Han Chinese who had completed the TPQ. No significant differences were demonstrated for TPQ HA scores, including the sub-scales, for subjects with different 5HTT-LPR genotypes. A significantly higher HA2 sub-score was demonstrated for subjects carrying the 10-12 5HTT-VNTR genotype, however, compared with those from the 12-12 genotype group, for the male population (P = 0.007). Our findings suggest that the 5HTT genetic polymorphism may be associated with HA scores; however, the effect is influenced by ethnicity and gender.

Prevalence of endothelial nitric oxide synthase gene polymorphisms in patients with atopic asthma.

Asthma is a common multifactorial disease, the aetiology of which is attributable to both environmental and genetic factors. The endothelial nitric oxide synthase (NOS3) gene has been implicated in asthma pathogenesis. This study investigated associations of 27 base-pair tandem repeat polymorphism in intron 4 and the Glu298Asp (G894T) variant of the NOS3 gene with atopic asthma in a Czech population. Polymerase chain reaction was used to determine the NOS3 genotypes in subjects with atopic asthma (n = 163) and random controls (n = 209). The NOS3 allele or genotype distributions did not differ significantly between the control and asthma groups. However, the common genotype (bb) of the NOS3 polymorphism in intron 4 was found to be significantly associated with total IgE levels (P = 0.006), specific IgE levels for feathers (P = 0.0002) and a positive skin prick test for hay (P = 0.004). In one atopic patient, we identified an additional 27-bp repeat in the NOS3 gene (NOS3c), which occurred in heterozygous combination with the NOS3b allele (NOS3b/c genotype). In addition, we describe a new polymorphism (A5495G) in the NOS3 gene, which was in almost complete linkage disequilibrium with the NOS3 repeat polymorphism in intron 4. The Glu298Asp variant was not associated with asthma and/or related atopic phenotypes in our study. Neither the NOS3 'b' allele nor the NOS3 'b/b' genotype showed any general association with atopic asthma, but they were associated with atopy-related phenotypes. We conclude that the NOS3 gene polymorphisms may act as disease modifiers in atopic asthma phenotype in our population.

The 27-bp Tandem Repeat Polymorphism in Intron 4 of the Endothelial Nitric Oxide Synthase Gene Is Not Associated with Coronary Artery Disease in a Hospital-Based Taiwanese Population

We studied whether the 27 base pair (bp) tandem repeat polymorphism in intron 4 of the endothelial nitric oxide synthase (eNOS) gene was associated with coronary artery disease (CAD) in a hospital-based Taiwanese population. We included 219 consecutive patients who underwent coronary angiography at our institution. Two alleles, containing 4 (eNOS4a) and 5 repeats (eNOS4b), were identified after polymerase chain reaction amplifying intron 4 of the eNOS gene. The genotype frequencies for eNOS4b/b, eNOS4a/b and eNOS4a/a were 77.9, 21.5 and 0.6% in CAD subjects, and 80, 20 and 0% in control subjects (Fisher’s exact test, p = 0.90), respectively. The odds ratio (OR) for CAD in patients with at least one eNOSa allele was 1.2 (0.5–2.9) after adjustment for classical CAD risk factors. The eNOS4a allele was not associated with the severity of CAD (Fisher’s exact test, p = 0.90) and the occurrence of acute myocardial infarction (AMI) or unstable angina (adjusted OR 0.6, 0.3–1.6) in patients with CAD. In conclusion, the 27-bp repeat polymorphism of the eNOS gene was not associated with CAD and the occurrence of AMI or unstable angina in a hospital-based Taiwanese population.

The polymorphic IL-1B and IL-1RN genes in the aetiopathogenesis of peptic ulcer.

Besides environmental factors, the genetic background of an individual may contribute to the development and final outcome of peptic ulcer disease. Interleukin-1beta (IL-1beta) and the interleukin-1 receptor antagonist (IL-1ra) are cytokines that play a key role in modulating the inflammatory response in the gastrointestinal mucosa. This study aimed to investigate whether polymorphisms in the IL-1B and IL-RN genes are involved in the susceptibility to and final outcome of peptic ulcer disease. DNA from 179 unrelated Spanish Caucasian patients with peptic ulcer diseases and 99 ethnically matched healthy controls was typed for the TaqI polymorphism at position + 3954 in the IL-1B gene and the variable number of tandem repeats polymorphism in intron 2 of the IL-1RN gene. The determination of Helicobacter pylori status and non-steroidal anti-inflammatory drug (NSAIDs) use was studied in all patients and in controls. H. pylori infection and NSAID use were more frequent in ulcer patients than in controls. There were no significant differences in carriage rate, genotype and allele frequencies of the IL-1RN and the IL-1B(+3954) gene polymorphisms between peptic ulcer patients and controls. However, a strong allelic association between IL-1B and IL-1RN genes was found in duodenal ulcer patients (P < 0.0006). Logistic regression identified H. pylori infection and NSAIDs use as independent risk factors for peptic ulcer diseases whereas the simultaneous carriage of IL-1B(+3954) allele 2 and IL-1RN allele 2 was associated with reduced risk for duodenal ulcer disease (OR: 0.37, 95% CI = 0.14-0.9). Our data suggest that IL-1B and IL-1RN genes in addition to bacterial and environmental factors play a key role in determining the final outcome of peptic ulcer disease.