Association between apolipoprotein E gene polymorphism and the risk of multiple sclerosis: A meta-analysis of 6977 subjects

Epidemiological studies have evaluated the association between apolipoprotein E (ApoE) gene polymorphism and multiple sclerosis (MS) risk. However, the results remain conflicting. Therefore, in order to derive a more precise association of ApoE gene polymorphism with MS risk, we performed this meta-analysis. Systematic searches of electronic databases PubMed, Embase and Web of Science, as well as hand searching of the references of identified articles were performed. Twenty studies were identified, covering a total of 4080 MS cases and 2897 controls. The results showed evidence for significant association between ApoE ε2 mutation and MS risk (for ε2/ε4 versus ε3/ε3: OR = 1.74, 95% CI = 1.12–2.71, p = 0.01; for ε2 allele versus ε3 allele: OR = 1.16, 95% CI = 1.01–1.35, p = 0.04). In the subgroup analysis by ethnicity, the similar results were obtained among Europeans (for ε2/ε4 versus ε3/ε3: OR = 1.81, 95% CI = 1.14–2.87, p = 0.01; for ε2 allele versus ε3 allele: OR = 1.19, 95% CI = 1.02–1.38, p = 0.03). After excluding the outlier studies by observing Galbraith plot, marginal association was found between ApoE ε3/ε4 genotype and the protective factor for MS (for ε3/ε4 versus ε3/ε3: OR = 0.86, 95% CI = 0.75–0.99, p = 0.04). In summary, the present meta-analysis provides evidence that ApoE ε2 mutation is associated with MS risk. In addition, ApoE ε3/ε4 genotype appears to be a protective factor for MS.     

Association of IL-6 − 174G > C and − 572C > G polymorphisms with risk of young ischemic stroke patients

Aim

To investigate the association between interleukin-6 (IL-6) − 174G > C and − 572C > G polymorphisms and risk for ischemic stroke (IS) in young patients.

Methods

We genotyped IL-6  − 174G > C and − 572C > G in a case–control study of 430 young IS patients and 461 control subjects. An unconditional multiple logistical regression model was used to calculate the effects of IL-6 − 174G > C and − 572C > G polymorphisms on IS risk.

Results

Higher body mass index, diabetes, hypertension, obesity, and smoking were associated with risk of ischemic stroke. Multivariate regression analyses showed that subjects carrying the − 174CC genotype (OR = 1.69, 95% CI = 1.16–2.57) and C allele (OR = 1.37, 95% CI = 1.09–1.67) had a small but significant increased risk of IS. Similarly, those carrying the − 572GG genotype (OR = 2.12, 95% CI = 1.18–3.82) and G allele (OR = 1.43, 95% CI = 1.14–1.83) had a moderate increased risk of IS. We found the − 174G > C and − 572C > G polymorphisms interact with hypertension and obesity.

Conclusion

Our results suggest that polymorphisms in IL-6 − 174G > C and − 572C > G are associated with IS risk in young patients, and that these polymorphisms interact with hypertension, obesity and etiologic subtypes. These findings could be helpful in identifying individuals at increased risk for developing IS.     

Association of ANRIL polymorphism (rs1333049:C>G) with myocardial infarction and its pharmacogenomic role in hypercholesterolemia

Single nucleotide polymorphisms (SNPs) of non-coding RNA in the INK4 locus (ANRIL) have been found to be associated with myocardial infarction (MI). However, the effect of rs1333049:C>G in INK4 locus in familial hypercholesterolemia patients and on lipid profile of the patients has not been studied in Pakistan. We therefore investigated the association of SNP rs1333049:C>G with MI as well as familial hypercholesterolemia patients and also determined the effect of genotype on lipid levels in a northern Pakistani population. A case–control association study was performed in which 611 individuals (294 patients, 290 healthy controls and 27 patients from hypercholesterolemia families) were genotyped for rs1333049:C>G, using an Allele specific polymerase chain reaction. We found a significant association of rs1333049:C>G with MI (χ² = 22.3, p < 0.001). The frequency of risk genotype CC was significantly different from the healthy controls (p < 0.001, χ² = 22.3). The risk allele C was at a higher frequency in the MI patients as compared to the controls (odds ratio [OR] = 1.55 (95% confidence interval [CI] = 1.22–1.96), p < 0.001). The logistic regression analysis for the genotype distribution resulted in strong association of risk allele C with MI under recessive model (OR = 3.17 (95% CI = 1.85–5.44) p < 0.001). When the data were further analyzed along the lines of gender, a significant association with both males and females was observed.     

Association study of CD36 single nucleotide polymorphisms with essential hypertension in the Northeastern Han Chinese

We found that cluster determinant 36 (CD36) gene is up-regulated in essential hypertension (EH) patients in our former research, but the association between CD36 gene variations and EH has not yet been clearly demonstrated. The relationship between CD36 gene single nucleotide polymorphisms (SNPs) and EH in the northeastern Han Chinese was examined in the present study through direct sequencing and genotype-detection. A total of 589 unrelated northeastern Han Chinese including 276 with EH and 313 controls were studied. SNPs in exon 7, exon 13 and intron 4 were detected using PCR-sequencing. The genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) or polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). + 216T/C, + 273A/G, + 132C/T, + 217T/C, + 212T/G and + 233T/C polymorphisms were identified. Distributions of genotypes AA, GA and GG of + 273A/G polymorphism were significantly different between EH group and the control group (χ²: 9.056, p = 0.011) and G allelic frequency was higher in EH (p = 0.006, OR = 1.629, 95% CI [1.224–2.168]). Logistic regression analysis showed that + 273A/G polymorphism was closely associated with blood pressure (BP) after adjusting for ages. When subclassified by sex, the genotype distribution of + 273A/G (p = 0.011) and allelic frequency of G allele (p = 0.006) were significantly different between EH participants and controls in males, but not in females. Subgroup analysis performed by body mass index (BMI) suggested that the genotype distribution of + 273A/G and allelic frequency were significantly different in non-obese group and non-obese men, but the associations were not significant (non-obese group: p = 0.016, OR = 1.664, 95% CI [1.459–2.409]; non-obese men: p = 0.073, OR = 1.898, 95% CI [1.033–3.487]). + 273A/G polymorphism in CD36 gene was associated with EH, and + 273G could be an independent predictor.     

Correlation of VEGF genetic polymorphisms and lipid profile to aortic calcification

Background

Aortic calcification is developed due to accumulation of a large amount of calcium in the aorta of the heart and it is the leading cause of aortic valve replacement and third leading cause of cardiovascular disease. The purpose of this study was to investigate the relation between aortic calcification and VEGF SNPs (− 2578C>A, − 1154G>A and + 936C>T) and to evaluate the association of these SNPs with biochemical parameter in relation to aortic calcification.

Methods

Aortic calcification was diagnosed by examining the posteroanterior chest X-rays by a radiologist and graded into four groups. The real-time polymerase chain reaction with melting curve analysis in LightCycler was used to genotype the VEGF SNPs.

Results

Among the VEGF SNPs, a significant genetic difference was found only between the aortic calcification and control group with VEGF SNP − 2578C>A but haplotypes T–A–A of (+ 936/− 1154/− 2578) were significantly different in control and aortic calcification and could enhance the aortic calcification development. By regression analysis, it was found that age, hypertension, diabetes, dyslipidemia, and hyperhomocysteinemia were found significantly different with the different genotypes of VEGF SNPs which may induce aortic calcification development.

Conclusion

Age, hypertension, diabetes, dyslipidemia, and hyperhomocysteinemia were established as aggravating factors for the aortic calcification in association with different VEGF genotypes.     

Apolipoprotein E Gene Polymorphism and Allele Frequencies in the Lebanese Population

Apolipoprotein E (ApoE) genotypes were studied in order to determine the prevalence in the Lebanese population and compare it with other populations. DNA from 160 unrelated healthy donors from our HLA-bank was used. ApoE genotype was determined using the CardioVascular Disease (CVD) StripAssay (this assay is based on a Polymerase Chain Reaction-Reverse Hybridization technique). The prevalence of genotypes E3/3, E3/4, and E2/3 was found to be 69%, 26%, and 22%, respectively, and 0.6% for each of E2/4 and E4/4 genotypes. The Lebanese population tested showed similarities to earlier reported ApoE genotypic distributions (high E3 allele frequency) but also peculiar differences especially to some Arabic countries (total absence of E2 allele among Saudis) and other populations. This is the first report from Lebanon that will serve as a template for future investigations of the prevalence of ApoE alleles in association with various clinical entities.     

The polymorphism − 1131T > C in apolipoprotein A5 gene is associated with dyslipidemia in Brazilian subjects

Background

Polymorphisms in apolipoprotein A5 gene (APOA5) have been associated with higher triglyceride levels in many populations. The aim of the study was to determine the allelic and genotypic distribution of the APOA5 − 1131T > C polymorphism and to identify the association of the genetic variant and the risk for dyslipidemia.

Methods

We genotyped 109 dyslipidemic subjects and 107 controls. The total cholesterol, triglycerides and HDL-c were determined enzymatically. Comparison of means among groups was calculated by ANOVA. Significant differences among groups were evaluated by Student–Newman–Keuls test.

Results

The minor allele C was more frequent in dyslipidemic subjects than controls (p = 0.019) and confers an increased individual risk for dyslipidemia (OR = 1.726, CI 95% = 1.095–2.721). The genotype analysis by gender showed that this allele was more frequent in dyslipidemic males (p = 0.037; OR = 2.050, CI 95% = 1.042–4.023). When participants were analyzed according to genotypes TT and TC/CC, C-carriers presented higher cholesterol and triglycerides levels than TT homozygous (p = 0.046 and 0.049, respectively).

Conclusions

The allele C confers higher total cholesterol and triglycerides levels in dyslipidemic adults. The APOA5 − 1131T > C polymorphism is associated with dyslipidemia in male subjects.     

Association between 1603C>T polymorphism of DBH gene and bipolar disorder in a Turkish population

Objectives

Dopamine-β-hydroxylase (DBH) is the enzyme responsible for the conversion of dopamine (DA) to norepinephrine (NE, noradrenaline) which is a key neurotransmitter in the central and peripheral nervous systems. Bipolar disorder is a major psychiatric disorder. The present study was designed to explore the associations of polymorphisms of DBH gene in Turkish patients with bipolar disorder.

Methods

− 1021C>T (rs1611115) polymorphism in promoter region, 444G>A (rs1108580) polymorphism in exon 2 and 1603C>T (rs6271; C535R) polymorphism in exon11 of DBH gene were analyzed in 106 patients with bipolar disorder and 106 healthy subjects by using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis.

Results

The results showed statistically significant associations for genotypic and allelic distribution between the 1603C>T polymorphism and bipolar disease (p = 0.0012 and p = 0.034, respectively). There was no association observed between the genotype and allelic frequencies for − 1021C>T and 444G>A polymorphisms and bipolar disorder.

Conclusions

Our data suggests that the 1603C>T polymorphism of the DBH gene is associated with susceptibility to bipolar disorder in a Turkish population.     

Apolipoprotein A5 T-1131C variant and risk for metabolic syndrome in obese adolescents

Background

Apolipoprotein A5 (APOA5) gene variants are associated with increased plasma triglycerides, a risk factor for metabolic syndrome (MS). The goal of the current study was the investigation of the distribution of T-1131C variant among obese adolescents with MS compared with healthy controls.

Subjects and methods

The study included 150 obese adolescents (75 males and 75 females) with MS and 204 age and sex matched normal healthy controls (100 males and 104 females). The mean age of the patients was 15.47 ± 2.54 years, ranged from 17 to 20 years. They were genotyped by polymerase chain reaction–restriction fragment length polymorphism for the mutation (T-1131C).

Results

The blood pressure, triglyceride and HOMA-R levels were significantly higher and HDL-C levels were significantly lower in carrier (TC + CC) compared to non-carrier (TT) MS patients. There was accumulation of − 1131C allele frequency in the MS group (31.33% vs. control group 11.76%), p < 0.001. The genotypes were in Hardy–Weinberg equilibrium both in the patients with metabolic syndrome and in the control subjects. Results of analysis of multiple regression models showed that the ApoA5 − 1131C carriers showed an increased incidence of MS (OR = 1.73, 95% CI: 1.41–2.11).

Conclusions

The present study suggests that the 1131T>C polymorphism is a risk factor for the development of metabolic syndrome in obese adolescents.     

Cyclooxygenase-2 169C > G and 8473T > C gene polymorphisms and prostaglandin E2 level in breast cancer: A case–control study

Aims

Cyclooxygenase 2 (COX-2) with the resulting prostaglandin E2 (PGE2) is linked to increased risk of human breast cancer (BC). The aim of this study was to determine COX-2 169C > G and 8473T > C gene polymorphisms and PGE2 level at various stages of BC clarifying the role of COX-2 gene polymorphism and PGE2 in relation to BC.

Methods

The study population comprised 160 women at different stages of BC and 150 gender- and age-matched healthy control subjects. Plasma PGE2 was measured by ELISA, the COX-2 gene polymorphisms were determined using PCR-RFLP.

Results

The variant alleles COX-2 169G and 8473C were significantly associated with BC susceptibility [OR = 3.1, 95% CI (2.2–4.4), P < 0.001 for 169C>G and OR = 1.74, 95%CI (1.3–2.4), P = 0.005 for 8473C]. However, both COX-2 gene polymorphisms were not associated with breast cancer stage. Plasma PGE2 levels were significantly increased in patients compared to the controls. In early and late stages of BC, there was a significant increase in the plasma PGE2 levels towards the presence of homozygous GG compared with homozygous CC (P < 0.001) for 169 C>G, also towards the presence of CC than TT (P < 0.001) for 8473T>C SNP.

Conclusion

The 169C>G and 8473T>C polymorphisms of the COX-2 gene were associated with the BC in Egyptian women. Furthermore, individuals with COX-2 169GG and 8473CC genotypes showed significant increase in plasma PGE2 levels. PGE2 levels may serve as a predictor of poor prognosis in patients with BC.     

Synergistic effect of anti and pro-inflammatory cytokine genes and their promoter polymorphism with ST-elevation of myocardial infarction

Background

The single-gene approach in association studies of polygenic diseases such as acute myocardial infarction (AMI) is likely to provide limited value. Interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) plasma levels may be genetically influenced.

Aim

We evaluate the impact of single nucleotide polymorphism of the promoter region of these genes, as well as reciprocal interaction of these genes with ST-elevation of myocardial infarction (STEMI).

Methods

In a case–control study 500 STEMI patients and 500 age- and sex-matched controls were studied. Three single-nucleotide polymorphism genotypes were evaluated by polymerase chain reaction and restriction enzyme analysis and assessed their association with STEMI. The synergistic effects of IL-6, TNF-α and IL-10 gene polymorphisms were evaluated by using logistic regression analysis.

Results

We found that IL-6 and TNF-α concentrations of studied population were significantly different (p < 0.0001) in each genotype of IL-6 − 174G>C and TNF-α − 308G>A gene polymorphisms respectively. A significant association was found in multivariate analysis for the IL-6 − 174G>C [odds ratio (OR): 0.390; 95% confidence interval (CI): 0.176–0.865, p = 0.020] and TNF-α − 308G>A [OR: 0.372; 95% CI: 0.171–808, p = 0.012] gene polymorphisms with STEMI. In contrast, IL-10 − 592C>A gene polymorphism was no longer significant in the multivariate model (OR: 0.678; 95% CI: 0.288 to 1.594, p = 0.373) whereas significant in univariate analysis (OR: 0.697; 95% CI: 0.523–0.929, p = 0.014).

Conclusions

Our findings suggest that IL-6, TNF-α and IL-10 gene polymorphisms all contribute in the association with STEMI whereas the association persisted only for IL-6 and TNF-α but not for IL-10 gene polymorphism with this disease in the multivariate analysis.     

Association of APOE, GCPII and MMP9 polymorphisms with common diseases and lipid levels in an older adult/elderly cohort

Background and aims

The characterization of candidate gene polymorphisms in elderly populations is an important tool for the identification of risk factors for age-related diseases and conditions. We aimed to genotype the APOE polymorphisms (rs429358 and rs7412), rs61886492 (1561C>T) and rs202720 of GCPII gene and rs3918242 (− 1562C>T) of MMP9 gene in an older-adult/elderly cohort from Cuiabá city, Mato Grosso Brazil as well as to characterize risk factors for morbidities and conditions affecting this cohort.

Methods

The studied population consisted of 570 subjects from Cuiabá city, Brazil, who were subjected to clinical interviews and blood collection for laboratory examinations and DNA extraction. Restriction Fragment Length Polymorphism Polymerase Chain Reaction (RFLP-PCR), sequence-specific primer PCR (SSP-PCR) and TaqMan® allelic discrimination assay were used for genotyping.

Results

The frequencies of APOE ε2 and ε4 were 6.6% and 14.8%, respectively, and the frequencies of GCPII rs61886492 T allele, GCPII rs202720 C allele and MMP9 rs3918242 T allele were, respectively, 3.0%, 26.6% and 10.1%. Significant associations between APOE ε2 allele with lower total cholesterol and LDL-cholesterol were found. In addition, MMP9 rs3918242 T allele was associated with higher LDL-cholesterol levels, suggesting a link between lipid metabolism alteration and cardiovascular disease.

Conclusions

The present findings contributed to characterize risk factors specific for the studied population and to better understand the molecular physiopathology of common morbidities and conditions affecting older-adult/elderly people.     

Polymorphisms of folate metabolism-related genes and survival of patients with colorectal cancer in the Korean population

Background

5-Fluorouracil (5-FU) is a cornerstone of chemotherapy for colorectal cancer (CRC), and the major targets of 5-FU are thymidylate synthase (TS), methylenetetrahydrofolate reductase (MTHFR), and reduced folate carrier 1 (RFC1). We hypothesized that polymorphisms in the genes encoding these proteins would be associated with CRC patient survival.

Patients and methods

We genotyped the following polymorphisms in 372 CRC patients: TS enhancer region (TSER), TS 1494del6, MTHFR 677C > T and 1298A > C, and RFC1 − 43T > C, 80G > A, and 696C > T. Using Kaplan–Meier curves, log-rank tests, and Cox proportional hazard models, we evaluated associations between these polymorphisms and overall survival (OS).

Results

The combined TS 1494 0bp6bp + 6bp6bp genotype was associated with reduced OS compared to the TS 1494 0bp0bp genotype. Among rectal cancer patients, the RFC1 − 43CC and 80AA genotypes were associated with favorable OS.

Conclusions

Our data suggest that TS and RFC1 polymorphisms are associated with CRC prognosis in Korean patients. Further studies are needed to verify these findings.     

The impact of GGH -401C > T polymorphism on cisplatin-based chemoradiotherapy response and survival in cervical cancer

Aims

Cervical cancer is the third most frequent cancer in women worldwide, mostly treated with cisplatin-based chemoradiotherapy. Since it is known that folate metabolism might interfere with cisplatin effectiveness, we intended to study the influence of the Gamma Glutamyl Hydrolase -401C > T polymorphism in treatment response in cervical cancer.

Methods

We retrospectively reviewed the clinical data of 167 patients with bulky cervical cancer submitted to cisplatin-based chemoradiotherapy. The genotypes of GGH -401C > T SNP were determined by real-time PCR and statistical analysis was performed by χ² test and survival analysis.

Results

The genotypes of GGH-401C > T were significantly associated with the response to platinum-based chemoradiotherapy. Treatment response was higher in patients carrying the CC genotype, who presented a significant increased chance of treatment response (survival time in months/genotype: 91 for CC Vs 72 for CT/TT; p = 0.035, log rank test). A Cox regression analysis accordingly showed that the presence of the T allele was significantly linked to a worse treatment response (HR = 3.036; CI 95% 1.032-8.934, p = 0.044).

Conclusions

The results of our study suggested the potential interest of GGH -401C > T as a predictive factor of the outcome of cervical carcinoma treated with cisplatin-based chemoradiotherapy.     

Tumor necrosis factor alpha − 308G>A, − 863C>A, − 857C>T gene polymorphisms and tuberculosis susceptibility: A meta-analysis

Background/aims

A large number of studies have shown that polymorphisms in the tumor necrosis factor-α (TNF-α, TNFA) gene are implicated in susceptibility to tuberculosis (TB). However, the results are inconsistent. We performed this meta-analysis to estimate the association between polymorphisms in the TNFA gene and TB susceptibility.

Methods

Relevant studies published before March 2012 were identified by searching PubMed, ISI web of knowledge, EBSCO and CNKI. The strength of relationship between the TNFA gene and TB susceptibility was assessed using odds ratios (ORs).

Results

A total number of twenty-three case–control studies including 3630 cases and 4055 controls were identified referring to three previously chosen single-nucleotide polymorphisms (SNPs): − 308G>A, − 863C>A and − 857C>T. No association was found between − 308G>A, − 863C>A and TB susceptibility: − 308G>A (GG + GA vs. AA): OR 0.85, 95%CI: 0.55–1.30, P = 0.44; − 863C>A (CC + CA vs. AA): OR 0.93, 95%CI: 0.84–1.81, P = 0.83. Increased risk of TB was associated with − 857C>T in the dominant genetic model (CC + CT vs. TT: OR 2.13, 95%CI: 1.25–3.63, P = 0.01), the heterozygote comparison (CT vs. TT: OR 2.69, 95%CI: 1.44–5.02, P = 0.00) and the homozygote comparison (CC vs. TT: OR 2.08, 95%CI: 1.22–3.53, P = 0.01) in Asian subjects.

Conclusion

There is an increased association between TNFA − 857C>T polymorphism and TB risk among Asian subjects. No association was found between − 308G>A and − 863C>A with TB risk. Due to several limitations in the present study, well-designed epidemiological studies with large sample size among different ethnicities should be performed in the future.     

Association of the + 45T > G adiponectin gene polymorphism with insulin resistance in non-diabetic Saudi women

Background

The human adiponectin gene variations are associated with obesity, insulin resistance, and diabetes. However, these associations have not been fully examined in a non-diabetic population in Saudi Arabia. We aimed to investigate the association of 45T > G single nucleotide polymorphism (SNP) in the adiponectin gene with total adiponectin levels, insulin resistance (IR), fasting blood glucose (FBG) and other markers of obesity in non-diabetic Saudi females.

Methods

One hundred non diabetic Saudi females were enrolled in this study. They were further divided according to their body mass index (BMI) into two groups. Group I, 46 non diabetic subjects with normal body weight and group II, 54 overweight and obese females. Adiponectin 45T/G polymorphism was detected by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP). Serum adiponectin was measured by ELISA.

Results

Obese women exhibited a higher distribution of TG/GG genotype compared with non-obese women. SNP + 45T > G genotypes were associated with higher FBG, insulin levels and HOMA–IR with lower total adiponectin levels in obese Saudi women. Otherwise the all estimated variables revealed non-significant differences among the non-obese genotypes. The observed differences in insulin resistance markers were very significant among women with a higher body weight but not among normal body weight women, thus suggesting that SNP + 45T > G effects on insulin sensitivity may depend upon body weight and body fat status.

Conclusion

SNP + 45T > G of adiponectin gene has a significant role in the development of insulin resistance in Saudi women possibly through an interaction with increase body weight and hypoadiponectinemia.     

Association of eNOS gene intron 4 a/b VNTR polymorphisms in children with nephrotic syndrome

To investigate the association of endothelial nitric oxide synthase gene intron 4 (eNOS4) polymorphisms with nephrotic syndrome, the eNOS4 genotypes were assessed in 161 children with nephrotic syndrome in comparison with 78 healthy subjects. We classified the children with nephritic syndrome into 2 groups: as steroid-sensitive nephrotic syndrome (SSNS) (n = 125) and steroid-resistant nephrotic syndrome (SRNS) (n = 36). The eNOS4 polymorphisms were analyzed by polymerase chain reaction. The frequencies of eNOS4 aa, ab and bb genotypes were 3%, 31%, and 66% in all the nephrotic syndrome groups, and 1%, 23%, and 76% in the control group (x² = 2.87, p > 0.05). In addition, the frequencies of eNOS4 aa, ab and bb genotypes were 2%, 33%, and 65% in SSNS group, and 5%, 28%, and 67% in the SRNS group (x² = 1.13, p = 0.567). The present study is the first to investigate eNOS4 gene polymorphisms in children with SSNS and SRNS. Our data show that the eNOS4 gene polymorphisms were not associated with the development, frequent relapse and response to steroid in nephritic syndrome.     

Cloning and expression analysis of novel Aux/IAA family genes in Gossypium hirsutum

The associations between polymorphisms of prostate stem cell antigen (PSCA-rs2294008C > T and -rs2976392G > A) and gastric cancer (GC) risk for Eastern Asians have been commonly studied, but the results were conflicting. The aim of the present study was to further assess the associations by the method of meta-analysis. The databases of Medline, Embase and CNKI (up to May 25th, 2011) were retrieved to identify eligible case-control studies. Odds ratio (OR) and 95% confidence interval (95%CI) were used to present the strength of the associations. In total, eight case-control studies in seven articles with 16792 individuals (9738 cases of GC and 7054 controls) were included in this meta-analysis. Through quantitative analyses, we found that T allele of rs2294008C > T and A allele of rs2976392G > A were significantly associated with increased GC risk [rs2294008C > T: OR (95%CI) = 1.31 (1.22-1.42), P_z-test < 0.001, P_{heterogeneity} = 0.166 for TT vs. C carriers; rs2976392G > A: OR (95%CI) = 1.36(1.24-1.50), P_z-test = 0.015, P_{heterogeneity} = 0.111 for AA vs. G carriers]. The results of subgroup analyses (according to histopathology, countries and sources of controls) indicated that T allele of rs2294008C > T and A allele rs2976392G > A were associated with increased risk of both intestinal- and diffuse-type GC, and associated with increased risk of GC for Chinese, Japanese, Koreans, PCC and HCC/PHCC. Furthermore, T allele of rs2294008C > T was also associated with increased risk of cardia and non-cardia GC, and associated with increased risk of GC for males and females. Besides those, this meta-analysis also indicated that the interactions between T allele of rs2294008C > T and A allele of rs2976392G > A was associated with increased risk of GC (A-T vs. G-T: OR = 1.16, 95%CI = 1.06-1.27, P_z-test = 0.001, P_{heterogeneity} = 0.835). Although modest limitations and potential bias cannot be eliminated, this meta-analysis suggests that PSCA -rs2294008C > T and -rs2976392G > A are potential factors of GC development for Eastern Asians, and future work may incorporate these findings and evaluate these variants as potential markers for screening and early diagnosis of GC.     

Uncoupling protein 2 − 866G/A and uncoupling protein 3 − 55C/T polymorphisms in young South African Indian coronary artery disease patients

Background

Uncoupling proteins (UCPs) 2 and 3 play an important role in the regulation of oxidative stress which contributes to chronic inflammation. Promoter polymorphisms of these genes have been linked to chronic diseases including heart disease and type II diabetes mellitus in several populations. This is the first investigation of the UCP2 − 866G/A rs659366 and UCP3 − 55C/T rs1800849 polymorphisms in young South African (SA) Indians with coronary artery disease (CAD).

Methods

A total of 300 subjects were recruited into this study of which 100 were SA Indian males with CAD, 100 age- (range 24–45 years), gender- and race-matched controls and 100 age-matched black SA males. The frequency of the UCP2 − 866G/A and UPC3 − 55C/T genotypes was assessed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP).

Results

The heterozygous UCP2 − 866G/A and homozygous UCP3 − 55C/C genotypes occurred at highest frequency in CAD patients (60% and 64%, respectively) compared to SA Indian controls (52% and 63%) and SA Black controls (50% and 58%). The UCP2 − 886G/A (OR = 1.110; 95% CI = 0.7438–1.655; p = 0.6835) and UCP3 − 55C/T (OR = 0.788; 95% CI = 0.482–1.289; p = 0.382) polymorphisms did not influence the risk of CAD.The rare homozygous UCP3 − 55T/T genotype was associated with highest fasting glucose (11.87 ± 3.7 mmol/L vs. C/C:6.11 ± 0.27 mmol/L and C/T:6.48 ± 0.57 mmol/L, p = 0.0025), HbA1c (10.05 ± 2.57% vs. C/C:6.44 ± 0.21% and C/T:6.76 ± 0.35%, p = 0.0006) and triglycerides (6.47 ± 1.7 mmol/L vs. C/C:2.33 ± 0.17 mmol/L and C/T:2.06 ± 0.25 mmol/L, p < 0.0001) in CAD patients.

Conclusion

The frequency of the UCP2 − 866G/A and UCP3 − 55C/T polymorphisms was similar in our SA Indian and SA Black groups. The presence of the UCP2 − 866G/A and UCP3 − 55C/T polymorphisms does not influence the risk of CAD in young South African Indian CAD patients.     

CD53, a suppressor of inflammatory cytokine production,is associated with population asthma risk via the functional promoter polymorphism − 1560 C>T

Background

In this study, the association of asthma with CD53, a member of the tetraspanin family, was assessed for the first time in a mechanism-based study.

Methods

Genetic polymorphisms of CD53 were analyzed in 591 subjects and confirmed in a replication study of 1001 subjects. CD53 mRNA and protein levels were measured in peripheral blood leukocytes, and the effects of the promoter polymorphisms on nuclear factor binding were examined by electrophoretic mobility shift assay. Cellular functional studies were conducted by siRNA transfections.

Results

Among tagging SNPs of CD53, the − 1560 C>T in the promoter region was significantly associated with asthma risk. Compared with the CC genotype, the CT and TT genotypes were associated with a higher asthma risk, with odd ratios of 1.74 (P = 0.009) and 2.03 (P = 0.004), respectively. These findings were confirmed in the replication study with odd ratios of 1.355 (P = 0.047) and 1.495 (P = 0.039), respectively. The − 1560 C>T promoter SNP had functional effects on nuclear protein binding as well as mRNA and protein expression levels in peripheral blood leukocytes. When CD53 was knocked down by siRNA in THP-1 human monocytic cells stimulated with house dust mite, the production of inflammatory cytokines as well as NFκB activity was significantly over-activated, suggesting that CD53 suppresses over-activation of inflammatory responses.

Conclusions

The − 1560 C>T SNP is a functional promoter polymorphism that is significantly associated with population asthma risk, and is thought to act by directly modulating nuclear protein binding, thereby altering the expression of CD53, a suppressor of inflammatory cytokine production.