Although numerous genetic studies have reported the link between Val66Met in BDNF gene with smoking, the findings remain controversial, mainly due to small-to-moderate sample sizes. The main aim of current investigation is to explore whether the variant of Val66Met has any genetic functions in the progress of smoking persistence. The Val-based dominant genetic model considering Val/* (namely, Val/Val + Val/Met) and Met/Met as two genotypes with comparison of the frequency of each genotype in current smokers and never smokers. There were seven genetic association articles including eight independent datasets with 10,160 participants were chosen in current meta-analytic investigation. In light of the potent effects of ethnicity on homogeneity across studies, we carried out separated meta-analyses according to the ancestry origin by using the wide-used tool of Comprehensive Meta-analysis software (V 2.0). Our meta-analyses results indicated that the Val66Met polymorphism was significantly linked with smoking persistence based on either all the chosen samples (N = 10,160; Random and fixed models: pooled OR = 1.23; 95% CI = 1.03–1.46; P value = 0.012) or Asian samples (N = 2,095; Fixed model: pooled OR = 1.25; 95% CI = 1.01–1.54; P value = 0.044; Random model: pooled OR = 1.25; 95% CI = 1.001–1.56; P value = 0.049). No significant clue of bias in publications or heterogeneity across studies was detected. Thus, we conclude that the Val66Met (rs6265) variant conveys genetic susceptibility to maintaining smoking, and smokers who carry Val/* genotypes have a higher possibility of maintaining smoking than those having Met/Met genotype.

尽管大量遗传学研究报道了BDNF中Val66Met之间的联系该基因与吸烟有关，研究结果仍存在争议，主要是由于样本量小到​​中等。当前研究的主要目的是探讨Val66Met的变异体在吸烟持续性过程中是否具有任何遗传功能。基于Val的优势遗传模型，将Val / *（即Val / Val + Val / Met）和Met / Met作为两个基因型，并比较了当前吸烟者和永不吸烟者每种基因型的频率。在当前的荟萃分析研究中，选择了7篇遗传协会文章，包括8个独立的数据集，共有10,160名参与者。考虑到族裔对整个研究的同质性的强大影响，我们使用广泛使用的综合荟萃分析软件（V 2.0）根据祖先的起源进行了分离的荟萃分析。N  = 10,160；随机和固定模型：合并OR = 1.23；95％CI = 1.03-1.46；P值= 0.012）或亚洲样本（N  = 2,095;固定模型：合并OR = 1.25; 95％CI = 1.01-1.54; P值= 0.044;随机模型：合并OR = 1.25; 95％CI = 1.001-1.56; P值= 0.049）。没有发现明显的出版物偏倚线索或跨研究的异质性。因此，我们得出的结论是，Val66Met（rs6265）变体传达了维持吸烟的遗传易感性，并且携带Val / *基因型的吸烟者比具有Met / Met基因型的吸烟者维持吸烟的可能性更高。