title: Association of 5-HTTLPR polymorphism with smoking behaviors: A meta-analysis.
abstract: Published articles reported controversial results about the association of 5-HTTLPR polymorphism with the risk of smoking behaviors. A meta-analysis was performed to assess the association between 5-HTTLPR polymorphism and smoking behaviors. A comprehensive search was conducted to identify studies (from January, 1990 to December, 2014) of the aforementioned association. The Q test and the I(2) statistic were used to examine between-study heterogeneity. Fixed or random effect model was selected based on heterogeneity test among studies. Meta-regression was used to explore the potential sources of between-study heterogeneity. Publication bias was estimated using funnel plots and Harbord test. Twenty-one published articles were included. Overall, we didn't find any significant association of 5-HTTLPR polymorphism with smoking initiation and smoking cessation in any of allele, dominant and recessive models. In the subgroup analysis stratified by ethnicity (Caucasian and Asian) or by whether smokers accepted the treatment for smoking cessation or not (Yes/No), there were still no significant associations detected in all genetic models. In conclusion, this meta-analysis suggested that there might be no association of 5-HTTLPR polymorphism with the risk of smoking behaviors. Further studies are needed to confirm these conclusions.
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Huijie
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Suyun
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Lulu
authors.initials: L
authors.lastname: Pan
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Fan
authors.initials: F
authors.lastname: Jiang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China.
authors.forename: Mingkui
authors.initials: M
authors.lastname: Han
authors.affiliation: Department of Epidemiology and Biostatistics, Shandong University, PR China. Electronic address: jiachongqi@sdu.edu.cn.
authors.forename: Chongqi
authors.initials: C
authors.lastname: Jia
mesh_terms: D044466:Asian People / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D011110:Polymorphism, Genetic; D012306:Risk; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012907:Smoking / Q000208:ethnology / Q000235:genetics*; D016540:Smoking Cessation; D044465:White People / Q000235:genetics
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins
keywords: 5-HTTLPR; Gene; Meta-analysis; Polymorphisms; Smoking cessation; Smoking initiation