Objective To investigate the association between MDM2 gene promoter SNP 309 polymorphism and leukemia susceptibility. Methods Such databases as Ovid, EBSCO, PubMed, CNKI, CBM, VIP and WanFang Data were searched to collect the case-control studies published from January 1990 to June 2012. According to the inclusion and exclusion criteria, the studies were screened, the data were extracted, and the methodological quality of the included studies was evaluated. Then meta-analysis was conducted using RevMan 5.0 and Stata 10.0 software, the pooled odds ratio (ORs) with 95% confidence interval (CI) were calculated, and the sensitivity and publication bias were evaluated at the same time. Results A total of 9 studies within 8 articles were included, which involved 1 821 cases and 5 642 controls. The results of meta-analysis showed that, the susceptibility of leukemia was increased in the G allele carriers compared with the T allele carriers (OR=1.26, 95%CI 1.08 to 1.46, P=0.003), and the leukemia risk was higher in the GG genotype populations compared with the TT genotype populations (OR=1.46, 95%CI 1.02 to 2.10, P=0.04). Among Asians with recessive models, the leukemia risk was higher in the homozygous GG genotype compared with both the heterozygous GT genotype and the homozygous TT genotype (OR=2.00, 95%CI 1.37 to 2.92, P=0.000 3). There was no obvious publication bias. Conclusion MDM2 gene promoter SNP 309 polymorphism is associated with the susceptibility of leukemia, and the G allele is likely to be the risk factor for leukemia.
Objective To investigate the correlation between MDM2 SNP309 and gastric cancer (GC) risk in Eastern Asian population. Methods Two reviewers independently searched MEDLINE, EMbase and CBM (from January 1st, 1990 to October 23rd, 2012) for case-control studies on the correlation between MDM2 SNP309 and GC risk in Eastern Asian population. Two reviewers independently screen literature, extracted the data, and assessed the methodological quality. Then meta-analysis was performed using RevMan 5.0 software. Results 5 case-control studies were finally included involving 1 621 GC cases and 2 639 controls. The pooled results showed that the variant homozygote (309GG genotype) was significantly associated with an increased risk of GC as compared to wild-type homozygote (309TT genotype: OR=1.54, 95% CI 1.04 to 2.29, P=0.02). Nevertheless, no association was found in comparison of variant heterozygote (309TG genotype) between wild-homozygote (309TT genotype: OR=1.03, 95% CI 0.75 to 1.42, P=0.006). A significantly increased risk of GC was observed for the recessive model (GG vs. TT/TG: OR=1.49, 95% CI 1.20 to 1.84, P=0.07). While in the dominant model (GG/TG vs. TT), non-significant association was observed (OR=1.18, 95% CI 0.84 to 1.65, P=0.001). Conclusion The MDM2 309GG may be significantly associated with an increased risk of GC among Eastern Asians.
Objective To systematically evaluate the correlation between endometriosis (EM) in Chinese women and Xba I polymorphism in intron-1 of estrogen receptor α (ER-α) gene. Methods Such databases as PubMed, MEDLINE, The Cochrane Library (Issue 3, 2012), VIP, CBM, WanFang Data and CNKI were searched to collect case-control studies about the correlation between EM and Xba I polymorphism in intron-1 of ER-α gene. The retrieval time was from 1980 to 2012. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted the data and assessed the quality, and then the meta-analysis was conducted by using RevMan 5.0 and Stata 12.0 software. Results A total of 7 studies involving 676 EM patients and 688 healthy volunteers were included. The results of meta-analyses showed that Chinese women with X/X genotype had similar risk of EM compared to those with x/x genotype (OR=0.95, 95%CI 0.58 to 1.54, P=0.82) or X/x genotype (OR=0.73, 95%CI 0.44 to 1.20, P=0.22). The allele X also showed similar risk of EM compared to the allele x (OR=1.11, 95%CI 0.93 to 1.33, P=0.25). Conclusion At present, it has not yet been found that the incidence of EM in Chinese women is related to the Xba I polymorphism in intron-1 of ER-α gene as well as the allele X. For the quantity and quality limitation of the included studies, this conclusion has to be proved by more studies.
Objective To systematically evaluate the correlation between type 2 diabetes mellitus (T2DM) in Chinese population and K121Q polymorphism in exon-4 of plasma cell glycoprotrin-1 (PC-1) gene. Methods The following databases such as CNKI, VIP, CBM, PubMed, EMbase, The Cochrane Library (Issue 3, 2012) and WanFang Data were searched to collect case-control studies on the correlation between T2DM and K121Q polymorphism in exon-4 of PC-1 gene. The retrieval time was from 1980 to 2012. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted the data and assessed the quality. Then the meta-analysis was conducted by using RevMan 5.0 and Stata 12.0 software, and the publication bias was analyzed by means of Egger’s linear regression. Results A total of 11 studies involving 1 637 T2DM patients and 1 730 healthy volunteers were included. The results of meta-analyses showed that, for Chinese population, the risk of T2DM was higher in those with K/Q genotype than K/K genotype (OR=1.84, 95%CI 1.19 to 2.85, P=0.006), in Q/Q+K/Q genotype than K/K genotype (OR=1.92, 95%CI 1.18 to 3.14, P=0.009), and also in allele Q than allele K (OR=1.83, 95%CI 1.16 to 2.89, P=0.010). Conclusion The K121Q polymorphism in exon-4 of PC-1 gene in Chinese population is significantly associated with T2DM. For the quantity and quality limitation of the included studies, this conclusion has to be further proved by more studies.
Objective To systematically review the correlation between epidermal growth factor (EGF) 61A/G polymorphism and the risk of esophageal carcinoma. Methods Such databases as PubMed, EMbase, CJFD, CBM, CNKI, VIP and WanFang Data were electronically searched from inception to January 1st, 2013, to collect case-control studies on the correlation between epidermal growth factor (EGF) 61A/G polymorphism and the risk of esophageal carcinoma. Two reviewers independently identified the literature according to inclusion and exclusion criteria, extracted data, and assessed the quality of the included studies. Then, meta-analysis was performed using RevMan 5.1 and Stata 12.0 software. Results A total of six studies involving 1 448 cases and 1 728 control subjects were included. The results of meta-analysis showed that, there was no significant association between EGF 61A/G polymorphism and the risk of esophageal carcinoma (dominant model: AG+GG vs. AA: OR=1.22, 95%CI 0.91 to 1.65; and recessive model: GG vs. AG+AA: OR=1.35, 95%CI 0.94 to 1.94; AG vs. AA: OR=1.12, 95%CI 0.93 to 1.35; GG vs. AA: OR=1.43, 95%CI 0.83 to 2.47). The results of subgroup analysis grouped by ethnicity showed that, EGF 61A/G polymorphism increased the risk of esophageal carcinoma of the White population (dominant model: AG+GG vs. AA: OR=1.39, 95%CI 1.14 to 1.71; and recessive model: GG vs. AG+AA: OR=1.75, 95%CI 1.37 to 2.25; GG vs. AA: OR=1.93, 95%CI 1.47 to 2.55). However, it had no correlation to the risk of esophageal carcinoma of Asian population. Conclusion Current studies showed that, EGF 61A/G polymorphism is not associated with susceptibility to esophageal carcinoma , but it may increase the risk of esophageal carcinoma in White population. Due to limited quality and quantity of the included studies, the above conclusion needs to be verified by more studies with large sample size.
Objective To systematically review the association between 14 bp insertion/ deletion polymorphism of HLA-G gene and preeclampsia (PE). Methods We electronically searched in the following databases: PubMed, Web of Science, EMbase, CBM, CNKI, WanFang Data, and VIP to collect all the case-control trials on the association between 14 bp insertion/ deletion polymorphism of HLA-G gene and PE. Two reviewers independently screened literature according to the inclusion and exclusion criteria, extracted data and assessed the quality of the included studies. Then, meta-analysis was performed using RevMan 5.1 software. Results Totally 10 studies were recruited. The results of meta-analysis showed that, the preeclampsia group was higher than the control group in the frequencies of HLA-G +14 bp haplotype in the fetus and fathers and the frequencies of HLA-G +14 bp/+14 bp genotype in fathers, but its frequencies of fetal HLA-G −14 bp haplotype was significantly lower. Their pooled OR and 95%CI were 1.42 (1.10 to 1.84), 1.54 (1.25 to 1.90), 2.00 (1.19 to 3.38), and 0.67 (0.54 to 0.82). Compared with the control group, in the preeclampsia group the frequencies of HLA-G +14 bp/+14 bp genotype in fetus were higher, while the frequencies of HLA-G −14 bp/−14 bp genotype were lower (OR=1.75, 95%CI 1.11 to 2.77; OR= 0.57, 95%CI 0.41 to 0.81). In the preeclampsia group, the frequencies of mother (+14 bp/−14 bp)/ fetal (+14 bp/+14 bp) were higher than the control group (OR= 3.77, 95%CI 1.40 to 10.11), while those of mother (−14 bp/−14 bp)/ fetal (−14 bp/−14 bp) and those of father (−14 bp/−14 bp)/fetal (−14 bp/−14 bp) were lower (OR=0.52, 95%IC 0.31 to 0.85; OR=0.33, 95%CI 0.15 to 0.75). Conclusion Paternal and fetal 14 bp insertion/ deletion polymorphism of HLA-G gene might be associated with preeclampsia. And maternal-fetal genotype compatibility analysis might provide new clues for the pathogenesis research and clinical diagnosis of preeclampsia.
Objective To evaluate the association between the Thr241Met polymorphism in the XRCC3 gene and the risk of lung cancer in Chinese population by meta-analysis. Methods Databases including PubMed, EMbase, CNKI, VIP and WanFang Data were searched to identify domestic and foreign case-control studies concerning the association between Thr241Met polymorphism in XRCC3 gene and the risk of lung cancer in Chinese population from the inception to August 20th, 2013. Two reviewers independently screened the literature according to the inclusion and exclusion criteria, extracted data and assessed quality. Then meta-analysis was performed using RevMan 5.0 software and Stata 10.0 software. Results A total of 5 case-control studies involved 2 999 lung cancer cases and 2 994 controls were included. The results of meta-analysis showed that, Chinese population who carry the variant genotype or allele had no increased risk of lung cancer: Met/Met vs. Thr/Thr: OR=1.00, 95%CI (0.38, 2.59), P=0.99; Met/Met vs. Thr/Met: OR=1.06, 95%CI (0.83, 1.36), P=0.63; Met/Met vs. Thr/Met+Thr/Thr: OR=0.99, 95%CI (0.38, 2.57), P=0.98; Thr/Met+Met/Met vs. Thr/Thr: OR=1.06, 95%CI (0.82, 1.37), P=0.65; Met vs. Thr: OR=1.05, 95%CI (0.82, 1.35), P=0.68. Conclusion Currently, Thr241Met polymorphism in the XRCC3 gene is not found to be associated with the risk of lung cancer in Chinese population. Considering the limited quality of the included case-control studies, more high quality studies with large sample size are needed to verify the above conclusion.
Objective To investigate the relationship between cyclooxygenase-2 (COX-2) gene polymorphism and genetic susceptibility to esophageal cancer. Methods The PubMed and EMbase databases were searched from the date of their establishment to January 1st, 2011 to collect the case-control studies on COX-2 polymorphism and susceptibility to esophageal cancer. For the population genotype distributions of both esophagus cancer group and control group, their odds ratios (ORs) and 95% confidence intervals (CIs) were taken as the effect indexes, either the fixed or random effect model was applied to conducted Meta-analysis in homozygote comparison, dominant and recessive genetic models, and the publication bias was assessed then. All statistical analyses were conducted with Stata11.0 software. Results A total of five case-control studies were included. The results of meta-analyses showed for the COX-2-765Ggt;C polymorphism, the CC+GC genotype was associated with the risk of esophageal cancer in a dominant genetic model (CC+GC vs. GG: OR=1.806, 95% CI 1.050 to 3.106); for the COX-2-1195Ggt;A polymorphism, the AA genotype was associated with the risk of esophageal cancer in homozygote comparison and recessive genetic models, the AA+GA genotype was associated with the risk of esophageal cancer in a dominant genetic model. Conclusion It is suggested that COX-2 polymorphism may be associated with genetic susceptibility to esophageal cancer.
Objective To explore whether the polymorphism of transforming growth factor β1 (TGF β1) gene at 869T/C and 915G/C loci contributes to the genetic susceptibility to hypertension. Methods Assessed under the same criteria, all case control studies on relationship between the polymorphism of TGF β1 gene and hypertension were searched in both English and Chinese databases. All articles retrieved were screened and evaluated, and meta-analyses were conducted with RevMan 5.1 software. Results A total of 14 case control studies were included. The results of meta-analyses showed TGF β1 gene C allele was related to hypertension (OR=1.37, 95%CI 1.21 to 1.54). It was noted that individuals with CC genotype and TT genotype had a significant increased risk of hypertension (OR=1.43, 95%CI 1.27 to 1.60; OR=0.64, 95%CI 0.53 to 0.78, respectively). And there was no b evidence showing that TGF β1 915G/C genetic polymorphism was related to hypertension. The results from meta-analyses of the studies based on Chinese population on the two loci were in consistent with the outcomes of overall meta-analyses. Sensitivity analyses indicated the results were stable. And publication bias was not present, reflected by P values from Egger’s regression asymmetry test and Begg’s adjusted rank correction test. Conclusions 869T/C polymorphism of TGF β1 gene is associated with hypertension. C allele is potentially one of the genetic risk factors for hypertension. Present studies do not support a direct relationship between 915G/C polymorphism TGF β1 gene and hypertension.
Objective To study the association between the insertion(I)/deletion(D) polymorphism of the angiotensin-converting enzyme gene intron 16 (ACE/ID) and diabetic nephropathy (DN) among Chinese population by Meta-analysis. Methods Odds ratios of ACE/ID genotype distributions were analyzed in NIDDM or IDDM patients with and without DN. All the related studies on ACE/ID polymorphism and DN were identified while poor-qualified studies were excluded, and the risk of publication bias was estiMetad. The Meta-analysis software, RevMan 3.1, was applied for investigating heterogeneity among individual studies and summarizing effects across studies by proper statistical methods. Result The pooled odds ratios (with 95%CI) of DD vs ID + II and II vs ID + DD were 2.17 (1.74-2.70) and 0.49 (0.36-0.66) in NIDDM (12 studies), 3.92 (2.05-7.47) and 0.19 (0.09-0.43) in IDDM (3 studies) respectively (Plt;0.01). Conclusion In both NIDDM and IDDM, ACE/ID polymorphism is believed to be associated with diabetic nephropathy. The number of DN patients with DD genotype has been increased while that with II genotype decreased.