A common biological basis of obesity and nicotine addiction
Contains fulltext : 128630.pdf (Publisher’s version ) (Open Access) Smoking influences body weight such that smokers weigh less than non-smokers and smoking cessation often leads to weight increase. The relationship between body weight and smoking is partly explained by the effect of nicotine on appetite and metabolism. However, the brain reward system is involved in the control of the intake of both food and tobacco. We evaluated the effect of single-nucleotide polymorphisms (SNPs) affecting body mass index (BMI) on smoking behavior, and tested the 32 SNPs identified in a meta-analysis for association with two smoking phenotypes, smoking initiation (SI) and the number of cigarettes smoked …
Sequence variants at CHRNB3-CHRNA6 and CYP2A6 affect smoking behavior
Contains fulltext : 89305.pdf (Publisher’s version ) (Closed access) Smoking is a common risk factor for many diseases. We conducted genome-wide association meta-analyses for the number of cigarettes smoked per day (CPD) in smokers (n = 31,266) and smoking initiation (n = 46,481) using samples from the ENGAGE Consortium. In a second stage, we tested selected SNPs with in silico replication in the Tobacco and Genetics (TAG) and Glaxo Smith Kline (Ox-GSK) consortia cohorts (n = 45,691 smokers) and assessed some of those in a third sample of European ancestry (n = 9,040). Variants in three genomic regions associated with CPD (P < 5 x 10(-8)), including previously identified SNPs at 15q25 repre…
Dopamine-related genes and spontaneous smoking cessation in ever-heavy smokers
Several studies have provided evidence for associations of polymorphisms located in and near dopamine-related genes and nicotine dependence and other smoking-related phenotypes, including pharmacogenetic interactions. Aim: The purpose of the present work was to examine the association of SNPs in the DOPA decarboxylase (DDC), dopamine receptor D2 (DRD2) and dopamine transporter (SLC6A3) genes with smoking cessation in a large retrospective study featuring approximately 900 cessation events. Materials & methods: Data originated from the enrollment questionnaire of the epidemiological ESTHER study of community-dwelling adults aged 50–74 years, conducted in the German state of Saarland bet…
Variants in COMT and spontaneous smoking cessation: retrospective cohort analysis of 925 cessation events
Genome-wide studies have identified single nucleotide polymorphisms associated with smoking behaviour and nicotine dependence. Less is known about genetic determinants of smoking cessation, but rs4680 in COMT has recently been shown to explain a substantial proportion of the variation in cessation in the general population. We attempted to replicate the reported, clinically relevant effect in a population-based retrospective cohort analysis of 1443 ever-heavy smokers, of whom 925 had reached abstinence. In Cox regression models, neither rs4680 nor two polymorphisms nearby were associated with smoking cessation. The adjusted relative cessation rate (95% confidence interval) in rs4680 methion…
Risk gene variants for nicotine dependence in the CHRNA5-CHRNA3-CHRNB4 cluster are associated with cognitive performance
Recent studies strongly support an association of the nicotinic acetylcholine receptor gene cluster CHRNA5-CHRNA3-CHRNB4 with nicotine dependence (ND). However, the precise genotype-phenotype relationship is still unknown. Clinical and epidemiological data on smoking behavior raise the possibility that the relevant gene variants may indirectly contribute to the development of ND by affecting cognitive performance in some smokers who consume nicotine for reasons of "cognition enhancement." Here, we tested seven single nucleotide polymorphisms (SNPs) rs684513, rs637137, rs16969968, rs578776, rs1051730, rs3743078, rs3813567 from the CHRNA5-CHRNA3-CHRNB4 gene cluster for association with ND, me…
Association of a variant in the muscarinic acetylcholine receptor 2 gene (CHRM2 ) with nicotine addiction
Genetic factors contribute to the overall risk of developing nicotine addiction, which is the major cause of preventable deaths in western countries. However, knowledge regarding specific polymorphisms influencing smoking phenotypes remains scarce. In the present study we provide evidence that a common single nucleotide polymorphism (SNP) in the 5′ untranslated region of CHRM2, the gene coding for the muscarinic acetylcholine receptor 2 is associated with nicotine addiction. CHRM2 was defined as a candidate gene for nicotine addiction based on previous evidence that linked variations in CHRM2 to alcohol and drug dependence. A total of more than 5,500 subjects representative of the German po…