Nicotine Addiction Development: From Epidemiology to Genetic Factors.

Background: Nicotine addiction is a complex and multifactorial disease affecting the central nervous system and consists of a set of characteristic symptoms and signs. Objective: The objective of this study was to provide an overview on smoking and the complexity of dependency, with special emphasis on the involvement of genetic factors, including neurexin and nicotinic cholinergic receptor genes. Methods: The following two aspects are discussed in the present article: (i) epidemiology in Mexico; and (ii) a review of the published literature on genetic association studies using the National Center for Biotechnology Information (NCBI) database of the USA as a search tool. The search key words were: nicotine, smoking, dependence, genetic, tobacco, neurobiology and GWAS. The publication period of the reviewed articles was January 2005 to July 2015. Results: There are numerous studies that provide evidence of the involvement of a genetic component that contributes to the risk of developing nicotine addiction, but the multifactorial nature of addiction requires coordinated research from multiple disciplines. Conclusion: Research is needed on the factors associated with genetic risk for nicotine addiction and their interaction with environmental factors.