1.
CR1 rs3818361 Polymorphism Contributes to Alzheimer's Disease Susceptibility in Chinese Population.
Li, Y, Song, D, Jiang, Y, Wang, J, Feng, R, Zhang, L, Wang, G, Chen, Z, Wang, R, Jiang, Q, et al
Molecular neurobiology. 2016;(6):4054-4059
Abstract
Recent genome-wide association studies (GWAS) reported CR1 rs3818361 polymorphism to be an Alzheimer's disease (AD) susceptibility variant in European ancestry. Three independent studies investigated this association in Chinese population. However, these studies reported weak or no significant association. Here, we reinvestigated the association using all the samples from three independent studies in Chinese population (N = 4047, 1244 AD cases and 2803 controls). We also selected three independent studies in European ancestry population (N = 11787, 3939 AD cases and 7848 controls) to evaluate the effect of rs3818361 polymorphism on AD risk in different ethnic backgrounds. In Chinese population, we did not identified significant heterogeneity using additive, recessive, and dominant genetic models. Meta-analysis showed significant association between rs3818361 and AD with P = 6.00E-03 and P = 5.00E-03. We further identified no heterogeneity of rs3818361 polymorphism between Chinese and European populations. We found that rs3818361 polymorphism contributed to AD with similar genetic risk in Chinese and European populations. In summary, this is the first study to show significant association between rs3818361 polymorphism and AD in Chinese population by a meta-analysis method. Our findings indicate that the effect of CR1 rs3818361 polymorphism on AD risk in Chinese cohorts is consistent with the increased risk observed in European AD cohorts.
2.
Lack of association between methionine synthase A2756G polymorphism and digestive system cancer risk: evidence from 3,9327 subjects.
Zhao, Y, Chen, Z, Ma, Y, Xia, Q, Zhang, F, Fu, D, Wang, XF
PloS one. 2013;(4):e61511
Abstract
BACKGROUND Polymorphisms in genes involved in the metabolism of folate and methyl groups have been implicated with risk of digestive system cancer. Methionine synthase (MTR) plays a central role in folate metabolism, thereby affecting DNA methylation. The association between A2756G polymorphism (rs1805087) in MTR and digestive system cancer susceptibility was inconsistent in previous studies. To investigate this inconsistency, we performed this meta-analysis. METHODS Databases including Pubmed, EMBASE, ISI Web of Science and China National Knowledge Infrastructure (CNKI) were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. Potential sources of heterogeneity were also assessed by subgroup analysis and meta-regression. RESULTS A total of 29 articles with 15,368 patients and 23,959 controls were included. We found no association between MTR A2756G polymorphism and digestive system cancer in overall population (G allele: OR = 1.03, 95% CI = 0.98-1.09, P = 0.25; dominant model: OR = 1.03, 95% CI = 0.97-1.10, P = 0.33; recessive model: OR = 1.02, 95% CI = 0.89-1.17, P = 0.79). In the stratified analyses according to cancer type, sample size and genotyping method, no evidence of any gene-disease association was obtained in almost all genetic models. However, marginal significant associations were found for East Asians and hospital-based studies. CONCLUSIONS This meta-analysis suggests that there is no significant association between the MTR A2756G polymorphism and digestive system cancer risk.