title: Association between chemokine receptor 5 (CCR5) delta32 gene variant and atherosclerosis: a meta-analysis of 13 studies.
abstract: BACKGROUND
  Chemokine receptor 5 (CCR5) is one of the pro-inflammatory G protein coupled receptors. Many studies have accessed the association between CCR5 gene polymorphism and atherosclerotic disease. However, the results are conflicting and inconclusive. The aim of this study was to evaluate the association more precisely.
  
  
  METHODS
  Trials were retrieved through Pubmed, Embase, Medline, China National Knowledge Infrastructure, Web of Science, and Cochrane database without restrictions on language. The pooled odds ratio (OR) and 95% confidence interval (CI) were used to describe the strength of association with atherosclerotic disease. The subgroup analysis was used to explore the heterogeneity bias among studies.
  
  
  RESULTS
  Data were obtained from 13 case-control studies that included 5321 patients with atherosclerotic disease and 4283 control subjects. In the overall analysis, the CCR5-delta32 (Δ32) genetic variants was not associated with increased the risk of atherosclerotic disease (dominant model: OR = 0.93, 95% CI = 0.69-1.24, I(2) = 77%, P = 0.60; recessive model: OR = 1.01, 95% CI = 0.61-1.65, I(2) = 0%, P = 0.98), even after stratification for the status of CCR5-delta32 allele. However, in subgroup analysis, the association was significant for Asians population (OR: 2.29, 95% CI: 1.44-3.64, P = 0.0004).
  
  
  CONCLUSIONS
  Our studies add to the evidence that CCR5 Δ32-positive genotype (Δ32/Δ32 or wt/Δ32) increases the risk of atherosclerotic disease in Asian population. Ethnicity difference might contribute to the inconsistency in isolated studies.
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Zhongwen
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Ju
authors.initials: J
authors.lastname: Liu
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Huanjun
authors.initials: H
authors.lastname: Wang
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Wu
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Xuanmei
authors.initials: X
authors.lastname: Wu
authors.affiliation: Qilu Hospital of Shandong University Jinan 250014, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Dong
authors.affiliation: Shandong Provincial Qianfoshan Hospital, Shandong University Jinan 250014, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liao
keywords: CCR5; atherosclerosis; gene polymorphism; meta-analysis