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Goldberg LR, Gould TJ. "Genetic influences impacting nicotine use and abuse during adolescence: insights from human and rodent studies". Brain Res Bull 2022; 187:24-38. [PMID: 35738503 DOI: 10.1016/j.brainresbull.2022.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 05/18/2022] [Accepted: 06/14/2022] [Indexed: 11/30/2022]
Abstract
Nicotine use continues to be a major public health concern, with an alarming recent rise in electronic cigarette consumption. Heritability estimates of nicotine use and abuse range from 40-80%, providing strong evidence that genetic factors impact nicotine addiction-relevant phenotypes. Although nicotine use during adolescence is a key factor in the development of addiction, it remains unclear how genetic factors impact adolescent nicotine use and abuse. This review will discuss studies investigating genetic factors impacting nicotine use during adolescence. Evidence from both rodent and human studies will be summarized and integrated when possible. Human adolescent studies have largely included candidate gene studies for genes identified in adult populations, such as genes involved in nicotine metabolism, nicotinic acetylcholine receptor signaling, dopaminergic signaling, and other neurotransmitter signaling systems. Alternatively, rodent studies have largely taken a discovery-based approach identifying strain differences in adolescent nicotine addiction-relevant behaviors. Here, we aim to answer the following three questions by integrating human and rodent findings: 1) Are there genetic variants that uniquely impact nicotine use during adolescence? 2) Are there genetic variants that impact both adolescent and adult nicotine use? and 3) Do genetic factors in adolescence significantly impact long-term consequences of adolescent nicotine use? Determining answers for these three questions will be critical for the development of preventative measures and treatments for adolescent nicotine use and addiction.
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Affiliation(s)
- Lisa R Goldberg
- Department of Biobehavioral Heatlh, Pennsylvania State University, University Park, PA, USA
| | - Thomas J Gould
- Department of Biobehavioral Heatlh, Pennsylvania State University, University Park, PA, USA.
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2
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Takahashi TT, Ornello R, Quatrosi G, Torrente A, Albanese M, Vigneri S, Guglielmetti M, Maria De Marco C, Dutordoir C, Colangeli E, Fuccaro M, Di Lenola D, Spuntarelli V, Pilati L, Di Marco S, Van Dycke A, Abdullahi RA, Maassen van den Brink A, Martelletti P. Medication overuse and drug addiction: a narrative review from addiction perspective. J Headache Pain 2021; 22:32. [PMID: 33910499 PMCID: PMC8080402 DOI: 10.1186/s10194-021-01224-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 03/12/2021] [Indexed: 12/27/2022] Open
Abstract
Chronic headache is particularly prevalent in migraineurs and it can progress to a condition known as medication overuse headache (MOH). MOH is a secondary headache caused by overuse of analgesics or other medications such as triptans to abort acute migraine attacks. The worsening of headache symptoms associated with medication overuse (MO) generally ameliorates following interruption of regular medication use, although the primary headache symptoms remain unaffected. MO patients may also develop certain behaviors such as ritualized drug administration, psychological drug attachment, and withdrawal symptoms that have been suggested to correlate with drug addiction. Although several reviews have been performed on this topic, to the authors best knowledge none of them have examined this topic from the addiction point of view. Therefore, we aimed to identify features in MO and drug addiction that may correlate. We initiate the review by introducing the classes of analgesics and medications that can cause MOH and those with high risk to produce MO. We further compare differences between sensitization resulting from MO and from drug addiction, the neuronal pathways that may be involved, and the genetic susceptibility that may overlap between the two conditions. Finally, ICHD recommendations to treat MOH will be provided herein.
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Affiliation(s)
- Tatiane Teru Takahashi
- Headache Research, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, King's College London, 20 Newcomen St, London, SE1 1YR, UK. .,Present address: Medicines Discovery Catapult, Block 35, Mereside, Alderley Park, Cheshire, SK10 4TG, UK.
| | - Raffaele Ornello
- Neuroscience Section, Department of Applied Clinical Sciences and Biotechnology, University of L'Aquila, Via Vetoio 1, Coppito, 67100, L'Aquila, Italy
| | - Giuseppe Quatrosi
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, Piazza delle Cliniche 2, 90127, Palermo, Italy
| | - Angelo Torrente
- Department of Biomedicine, Neurosciences and Diagnostic (Bi.N.D.), University of Palermo, Via del Vespro 129, 90127, Palermo, Italy
| | - Maria Albanese
- Department of Systems Medicine, University of Rome "Tor Vergata"; Neurology Unit, "Tor Vergata" Hospital, Viale Oxford, 81, 00133, Rome, Italy
| | - Simone Vigneri
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Via del Vespro, 129, 90127, Palermo, Italy.,Pain Medicine Unit, Santa Maria Maddalena Hospital, Occhiobello, Italy
| | - Martina Guglielmetti
- Regional Headache Referral Center, Sant'Andrea Hospital, Via di Grottarossa 1039, 00189, Rome, Italy.,Department of Medical, Surgical and Experimental Sciences, University of Sassari, Piazza Università, 21, 07100, Sassari, Italy
| | - Cristiano Maria De Marco
- Regional Headache Referral Center, Sant'Andrea Hospital, Via di Grottarossa 1039, 00189, Rome, Italy
| | - Camille Dutordoir
- Department of Neurology, University Hospital Ghent, Corneel Heymanslaan 10, 9000, Ghent, Belgium
| | - Enrico Colangeli
- Present address: Medicines Discovery Catapult, Block 35, Mereside, Alderley Park, Cheshire, SK10 4TG, UK
| | - Matteo Fuccaro
- Department of Neurology, Conegliano Hospital, Via Brigata Bisagno, 2, 31015, Conegliano, Italy
| | - Davide Di Lenola
- Department of Medico-Surgical Sciences and Biotechnologies, "Sapienza" University of Rome, Polo Pontino, Viale XXIV Maggio 7, 04100, Latina, Italy
| | - Valerio Spuntarelli
- Division of Pharmacology, Department of Internal Medicine, Erasmus MC University Medical Centre Rotterdam, Wytemaweg 80, 3015, CN, Rotterdam, The Netherlands
| | - Laura Pilati
- Department of Biomedicine, Neurosciences and Diagnostic (Bi.N.D.), University of Palermo, Via del Vespro 129, 90127, Palermo, Italy
| | - Salvatore Di Marco
- Department of Biomedicine, Neurosciences and Diagnostic (Bi.N.D.), University of Palermo, Via del Vespro 129, 90127, Palermo, Italy
| | - Annelies Van Dycke
- Department of Neurology, AZ Sint-Jan Brugge, Ruddershove 10, 8000, Brugge, Belgium
| | - Ramla Abuukar Abdullahi
- Headache Research, Wolfson CARD, Institute of Psychiatry, Psychology & Neuroscience, King's College London, 20 Newcomen St, London, SE1 1YR, UK.,Headache Centre, Guy's and St Thomas NHS Trust, London, UK
| | | | - Paolo Martelletti
- Regional Headache Referral Center, Sant'Andrea Hospital, Via di Grottarossa 1039, 00189, Rome, Italy.,Department of Clinical and Molecular Medicine, Sapienza University of Rome, Via di Grottarossa 1039, 00189, Rome, Italy
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Ruzilawati AB, Islam MA, Muhamed SKS, Ahmad I. Smoking Genes: A Case-Control Study of Dopamine Transporter Gene ( SLC6A3) and Dopamine Receptor Genes ( DRD1, DRD2 and DRD3) Polymorphisms and Smoking Behaviour in a Malay Male Cohort. Biomolecules 2020; 10:biom10121633. [PMID: 33287325 PMCID: PMC7761729 DOI: 10.3390/biom10121633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 11/29/2020] [Accepted: 11/30/2020] [Indexed: 12/17/2022] Open
Abstract
Dopamine receptor and dopamine transporter genes polymorphisms have been associated with cigarette smoking behaviour in different populations. The aim of this case-control study was to evaluate polymorphisms in the dopamine transporter gene (SLC6A3 (rs27072)) and the dopamine receptor genes (DRD1 (rs686), DRD2 (rs1800497) and DRD3 (rs7653787)) and their contribution to smoking behaviour in a Malay male population. We identified 476 participants over the age of 18 years comprising 238 smokers and 238 non-smokers. Information such as age, height, weight, body mass index, systolic and diastolic blood pressures, marital status, and smoking status of close family members were taken. For the genetic study, we genotyped four genes (SLC6A3 (rs27072), DRD1 (rs686), DRD2 (rs1800497) and DRD3 (rs7653787)) using the polymerase chain reaction-restriction fragment length polymorphism method and further confirmed our findings with sequencing. Dopamine receptor genes (DRD1, DRD2 and DRD3) were found to be associated with smoking behaviour in a Malay male population. The dopamine transporter gene (SLC6A3) did not show this association. Significant differences were observed between smokers' and non-smokers' age, systolic blood pressure, marital status and family members who smoke. Smoking behaviour is significantly influenced by genetic variations of DRD1, DRD2 and DRD3 in a Malay male population.
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Affiliation(s)
- Abu Bakar Ruzilawati
- Department of Pharmacology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia; (A.B.R.); (S.K.S.M.)
| | - Md Asiful Islam
- Department of Haematology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia;
| | - Siti Khariem Sophia Muhamed
- Department of Pharmacology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia; (A.B.R.); (S.K.S.M.)
| | - Imran Ahmad
- Department of Family Medicine, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian 16150, Kelantan, Malaysia
- Correspondence:
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Salatino-Oliveira A, Rohde LA, Hutz MH. The dopamine transporter role in psychiatric phenotypes. Am J Med Genet B Neuropsychiatr Genet 2018; 177:211-231. [PMID: 28766921 DOI: 10.1002/ajmg.b.32578] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 06/26/2017] [Accepted: 07/18/2017] [Indexed: 01/06/2023]
Abstract
The dopamine transporter (DAT) is one of the most relevant and investigated neurotransmitter transporters. DAT is a plasma membrane protein which plays a homeostatic role, controlling both extracellular and intracellular concentrations of dopamine (DA). Since unbalanced DA levels are known to be involved in numerous mental disorders, a wealth of investigations has provided valuable insights concerning DAT role into normal brain functioning and pathological processes. Briefly, this extensive but non-systematic review discusses what is recently known about the role of SLC6A3 gene which encodes the dopamine transporter in psychiatric phenotypes. DAT protein, SLC6A3 gene, animal models, neuropsychology, and neuroimaging investigations are also concisely discussed. To conclude, current challenges are reviewed in order to provide perspectives for future studies.
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Affiliation(s)
| | - Luis A Rohde
- Division of Child and Adolescent Psychiatry, Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Institute for Developmental Psychiatry for Children and Adolescents, São Paulo, Brazil
| | - Mara H Hutz
- Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
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Hirata T, Uemura T, Shinohara M, Hirano M. Association between Dopamine Transporter Gene (<i>DAT1</i>) Polymorphisms and Eating Disorders with Binge Eating Behavior. ACTA ACUST UNITED AC 2017. [DOI: 10.4236/ojpsych.2017.74028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Bieliński M, Jaracz M, Lesiewska N, Tomaszewska M, Sikora M, Junik R, Kamińska A, Tretyn A, Borkowska A. Association between COMT Val158Met and DAT1 polymorphisms and depressive symptoms in the obese population. Neuropsychiatr Dis Treat 2017; 13:2221-2229. [PMID: 28860780 PMCID: PMC5571853 DOI: 10.2147/ndt.s138565] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVES Depressive symptoms are common among patients with obesity. Abnormalities in dopamine signaling involved in the reward circuit may ensue excessive consumption of food, resulting in obesity and leading to neuropsychiatric disorders such as depression. This study sought to investigate the association of polymorphisms in the genes encoding DAT1/SLC6A3 and COMT with the intensity of depressive symptoms in obese subjects. PARTICIPANTS AND METHODS Prevalence and severity of depressive symptoms were assessed in a group of 364 obese patients using the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale (HDRS). Genetic polymorphisms in DAT1 and COMT were evaluated in peripheral blood samples. RESULTS The results indicated an association between DAT1 alleles and depressive symptoms, as well as severity of obesity. Subjects homozygous for the nine-repeat allele scored higher in BDI (P=0.022) and HDRS (P=0.00001), suggesting higher intensity of depression in both sexes. This allele was also associated with the highest body mass index (BMI; P=0.001). Carriers of the Val158Met allele of COMT scored higher on both depression scales (BDI, P=0.0005; HRDS, P=0.002) and had the highest BMI values. CONCLUSION Polymorphisms in the DAT1 and COMT genes are associated with a greater intensity of depressive symptoms in the obese population.
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Affiliation(s)
- Maciej Bieliński
- Department of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz
| | - Marcin Jaracz
- Department of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz
| | - Natalia Lesiewska
- Department of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz
| | - Marta Tomaszewska
- Department of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz
| | - Marcin Sikora
- Department of Biotechnology, Nicolaus Copernicus University in Toruń, Toruń
| | - Roman Junik
- Department of Endocrinology and Diabetology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland
| | - Anna Kamińska
- Department of Endocrinology and Diabetology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland
| | - Andrzej Tretyn
- Department of Biotechnology, Nicolaus Copernicus University in Toruń, Toruń
| | - Alina Borkowska
- Department of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń, Collegium Medicum in Bydgoszcz, Bydgoszcz
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Li S, Wang Q, Pan L, Li H, Yang X, Jiang F, Zhang N, Han M, Jia C. The association of dopamine pathway gene score, nicotine dependence and smoking cessation in a rural male population of Shandong, China. Am J Addict 2016; 25:493-8. [PMID: 27490263 DOI: 10.1111/ajad.12421] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/16/2016] [Accepted: 07/25/2016] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Smoking and smoking cessation are both psychological and physiological traits. We aimed to investigate the interaction between dopamine pathway gene scores and nicotine dependence on smoking cessation in a rural Chinese male population. METHODS Participants were recruited from 17 villages in Shandong, China. DNA was extracted from blood sample of 819 participants. 25 single nucleotide polymorphisms (SNPs) in 8 dopamine (DA) pathway genes were genotyped. Weighted gene score of each gene is used to analyze the whole gene effect. Logistic regression was used to calculate odds ratios (OR) and multivariate-adjusted OR of each gene score for smoking cessation. Multiplicative model interaction was assessed through a cross-product interaction term of gene score by nicotine dependence in a multivariate logistic regression model. RESULTS After adjusting for age, occupation, education, marital status, self-rating anxiety score, and disease status, we observed significant negative associations of catechol-O-methyltransferase (COMT), dopamine receptor D2 (DRD2) gene score and smoking cessation, as well as significant positive associations between ankyrin repeat and kinase domain containing 1 (ANKK1), dopamine transporter (SLC6A3), dopamine receptor D4 (DRD4) gene score and smoking cessation. A significant multiplicative model interaction between nicotine dependence and the SLC6A3 gene score on smoking cessation was also observed (p = .03). CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE There is a significant multiplicative model interaction of SLC6A3 gene score and nicotine dependence on smoking cessation. This finding could help to identify smokers who may be at high risk of relapse, and thus to develop more professional and personalized smoking cessation treatment. (Am J Addict 2016;25:493-498).
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Affiliation(s)
- Suyun Li
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Qiang Wang
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Lulu Pan
- Hebei Center for Disease Control and Prevention, Hebei, P. R. China
| | - Huijie Li
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Xiaorong Yang
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Fan Jiang
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Nan Zhang
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Mingkui Han
- Department of Epidemiology, Shandong University, Jinan, P. R. China
| | - Chongqi Jia
- Department of Epidemiology, Shandong University, Jinan, P. R. China
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8
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Choi HD, Shin WG. Meta-analysis update of association between dopamine transporter SLC6A3 gene polymorphism and smoking cessation. J Health Psychol 2016; 23:1250-1257. [PMID: 27287604 DOI: 10.1177/1359105316648479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The SLC6A3 gene is involved in the dopamine pathway, which influences smoking behavior. This study was conducted to present updated results of a meta-analysis to evaluate the association between SLC6A3 polymorphism and smoking cessation. In total, eight studies were assessed, and 9-repeat alleles and no 9-repeat alleles were compared by smoking cessation outcomes. No significant association between SLC6A3 genotype and smoking cessation was observed for the main analysis (odds ratio = 1.128; 95% confidence interval = 0.981-1.298). In conclusion, the genetic variations in SLC6A3 are not associated with smoking cessation, which is not consistent with the results of the previous meta-analysis.
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Johnson SL, Carver CS, Joormann J, Cuccaro ML. Genetic polymorphisms related to behavioral approach and behavioral inhibition scales. PERSONALITY AND INDIVIDUAL DIFFERENCES 2016. [DOI: 10.1016/j.paid.2015.09.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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10
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Meta-analysis reveals significant association of 3'-UTR VNTR in SLC6A3 with smoking cessation in Caucasian populations. THE PHARMACOGENOMICS JOURNAL 2015; 16:10-7. [PMID: 26149737 PMCID: PMC4705003 DOI: 10.1038/tpj.2015.44] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 03/29/2015] [Accepted: 05/18/2015] [Indexed: 12/11/2022]
Abstract
Many studies have examined the association between SLC6A3 3′-UTR VNTR polymorphism and smoking cessation; however, the results are inconclusive, primarily because of the small to moderate-size samples. The primary goal of this study was to determine whether this polymorphism has any effect on smoking cessation by a meta-analysis of all reported studies. We adopted a 9-repeat dominant model that considers 9-repeat and non 9-repeat as two genotypes and compared their frequencies in former vs. current smokers. Eleven studies with 5,480 participants were included. Considering the presence of study heterogeneity and differences in the availability of information from each study, three separate meta-analyses were performed with the Comprehensive Meta-Analysis statistical software (v. 2.0). The first meta-analysis provided evidence of association between the 9-repeat genotype and smoking cessation under the fixed-effects model (pooled odds ratio [OR] 1.13; 95% confidence interval [CI] 1.01, 1.27; P = 0.037) but not in the random-effects model (pooled OR 1.11; 95% CI 0.96, 1.29; P = 0.159). Given the marginal evidence of heterogeneity among studies (P = 0.10; I2 = 35.9%), which likely was caused by inclusion of an Asian-population treatment study with an opposite effect of the polymorphism on smoking cessation, we excluded these data, revealing a significant association between the 9-repeat genotype and smoking cessation under both the fixed- and random-effects models (pooled OR 1.15; 95% CI 1.02, 1.29; P = 0.02 for both models). By analyzing adjusted and unadjusted results, we performed the third meta-analysis, which showed consistently that the 9-repeat genotype was significantly associated with smoking cessation under both the fixed- and random-effects models (pooled OR 1.17; 95% CI 1.04, 1.31; P = 0.009 for both models). We conclude that the 3′-UTR VNTR polymorphism is significantly associated with smoking cessation, and smokers with one or more 9-repeat alleles have a 17% higher probability of smoking cessation than smokers carrying no such allele.
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Genetic variants and early cigarette smoking and nicotine dependence phenotypes in adolescents. PLoS One 2014; 9:e115716. [PMID: 25545355 PMCID: PMC4278712 DOI: 10.1371/journal.pone.0115716] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 11/30/2014] [Indexed: 01/16/2023] Open
Abstract
Background While the heritability of cigarette smoking and nicotine dependence (ND) is well-documented, the contribution of specific genetic variants to specific phenotypes has not been closely examined. The objectives of this study were to test the associations between 321 tagging single-nucleotide polymorphisms (SNPs) that capture common genetic variation in 24 genes, and early smoking and ND phenotypes in novice adolescent smokers, and to assess if genetic predictors differ across these phenotypes. Methods In a prospective study of 1294 adolescents aged 12–13 years recruited from ten Montreal-area secondary schools, 544 participants who had smoked at least once during the 7–8 year follow-up provided DNA. 321 single-nucleotide polymorphisms (SNPs) in 24 candidate genes were tested for an association with number of cigarettes smoked in the past 3 months, and with five ND phenotypes (a modified version of the Fagerstrom Tolerance Questionnaire, the ICD-10 and three clusters of ND symptoms representing withdrawal symptoms, use of nicotine for self-medication, and a general ND/craving symptom indicator). Results The pattern of SNP-gene associations differed across phenotypes. Sixteen SNPs in seven genes (ANKK1, CHRNA7, DDC, DRD2, COMT, OPRM1, SLC6A3 (also known as DAT1)) were associated with at least one phenotype with a p-value <0.01 using linear mixed models. After permutation and FDR adjustment, none of the associations remained statistically significant, although the p-values for the association between rs557748 in OPRM1 and the ND/craving and self-medication phenotypes were both 0.076. Conclusions Because the genetic predictors differ, specific cigarette smoking and ND phenotypes should be distinguished in genetic studies in adolescents. Fifteen of the 16 top-ranked SNPs identified in this study were from loci involved in dopaminergic pathways (ANKK1/DRD2, DDC, COMT, OPRM1, and SLC6A3). Impact Dopaminergic pathways may be salient during early smoking and the development of ND.
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12
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Ohmoto M, Takahashi T, Kubota Y, Kobayashi S, Mitsumoto Y. Genetic influence of dopamine receptor, dopamine transporter, and nicotine metabolism on smoking cessation and nicotine dependence in a Japanese population. BMC Genet 2014; 15:151. [PMID: 25526961 PMCID: PMC4307219 DOI: 10.1186/s12863-014-0151-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/11/2014] [Indexed: 01/04/2023] Open
Abstract
Background This study investigated whether polymorphisms of the ankyrin repeat and kinase domain containing 1 gene (ANKK1), which is adjacent to the dopamine D2 receptor gene (DRD2), and the dopamine transporter (SLC6A3) and cytochrome P450 2A6 (CYP2A6) genes influence smoking cessation and nicotine dependence in a Japanese population. In 96 current and former smokers, genotyping frequencies for the ANKK1/DRD2 TaqIA, SLC6A3 VNTR, and CYP2A6 polymorphisms were subjected to chi-square analysis, and regression analyses were used to determine the association of the genotypes of current smokers with a Heavy Smoking Index, in addition to evaluating the effect of the subjects’ smoking history on the association. Results Genotyping results suggested that nicotine dependence among current smokers homozygous for the SLC6A3 10r allele was lower than that of smokers carrying the minor alleles, and that the CYP2A6 polymorphism might mediate this association. Furthermore, the age at which current smokers began smoking might moderate the association between their genetic polymorphisms and nicotine dependence. Conclusions This study provides preliminary findings on the influence of genetic variants on the smoking phenotypes in a Japanese population.
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Affiliation(s)
- Masanori Ohmoto
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa, 920-1181, Japan.
| | - Tatsuo Takahashi
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa, 920-1181, Japan.
| | - Yoko Kubota
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa, 920-1181, Japan.
| | - Shinjiro Kobayashi
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa, 920-1181, Japan.
| | - Yasuhide Mitsumoto
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa, 920-1181, Japan.
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13
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Hiemstra M, Engels RCME, Barker ED, van Schayck OCP, Otten R. Smoking-specific parenting and smoking onset in adolescence: the role of genes from the dopaminergic system (DRD2, DRD4, DAT1 genotypes). PLoS One 2013; 8:e61673. [PMID: 23637880 PMCID: PMC3630129 DOI: 10.1371/journal.pone.0061673] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 03/12/2013] [Indexed: 11/24/2022] Open
Abstract
Although only few studies have shown direct links between dopaminergic system genes and smoking onset, this does not rule out the effect of a gene-environment interaction on smoking onset. Therefore, the aim of this study was to examine the associations between smoking-specific parenting (i.e., frequency and quality of communication and house rules) and smoking onset while considering the potential moderating role of dopaminergic system genes (i.e., DRD2, DRD4, and DAT1 genotypes). Data from five annual waves of the 'Family and Health' project were used. At time 1, the sample comprised 365 non-smoking adolescents (200 younger adolescents, mean age = 13.31, SD = .48; 165 older adolescents, mean age = 15.19, SD = .57). Advanced longitudinal analyses were used (i.e., logistic regression analyses, (dual) latent growth curves, and cross-lagged path models). The results showed a direct effect of quality of communication on smoking onset. No direct effects were found for frequency of communication and house rules. Furthermore, no direct and moderating effects of the DRD2, DRD4, or DAT1 genotypes were found. In conclusion, the findings indicated that the effects of smoking-specific parenting on smoking are similar for adolescent carriers and non-carriers of the dopaminergic system genes.
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Affiliation(s)
- Marieke Hiemstra
- Behavioural Science Institute, Radboud University Nijmegen, Nijmegen, The Netherlands.
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Thomson CJ, Carlson SR, Rupert JL. Association of a common D3 dopamine receptor gene variant is associated with sensation seeking in skiers and snowboarders. JOURNAL OF RESEARCH IN PERSONALITY 2013. [DOI: 10.1016/j.jrp.2012.11.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Gordiev M, Engstrom PF, Khasanov R, Moroshek A, Sitdikov R, Dgavoronkov V, Schnoll RA. Genetic Analysis of Polymorphisms in Dopamine Receptor and Transporter Genes for Association with Smoking among Cancer Patients. Eur Addict Res 2013; 19:105-11. [PMID: 23128675 PMCID: PMC3649069 DOI: 10.1159/000341711] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Accepted: 07/07/2012] [Indexed: 01/14/2023]
Abstract
BACKGROUND Smoking among Russian cancer patients may be related to variations in the DRD2/ANKK1 (Taq1), DRD4 (exon III VNTR), and SLC6A3 genes. METHODS Seven hundred fifty patients provided smoking history and DNA. RESULTS Current smokers were more likely to be DRD2 A2 allele carriers versus nonsmokers (former/never smokers; 69 vs. 56%; OR = 1.69; 95% CI 1.13-2.53, p = 0.01) and former smokers (69 vs. 59%; OR = 1.54; 95% CI 0.97-2.46, p = 0.07). Ever smokers (current/former smokers) were more likely to be DRD2 A2 allele carriers versus never smokers (65 vs. 55%; OR = 1.50; 95% CI 1.00-2.27, p = 0.05). The risk of current smoking among DRD2 A2 allele carriers was present if the DRD4 short allele was also present (OR = 1.76; 95% CI 1.12-2.78, p = 0.02), and the risk of ever smoking among DRD2 A2 allele carriers was present if the DRD4 short allele was also present (OR = 1.62; 95% CI 1.02-2.55, p = 0.04). DRD2 A2 allele carriers had a shorter period of previous abstinence versus DRD2 A1 carriers (p = 0.02). Effects were not statistically significant when controlling for multiple comparisons. CONCLUSIONS The DRD2 A2 allele may increase the risk of smoking among cancer patients, convergent with studies using non-Western samples. However, additional replication is needed.
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Affiliation(s)
- Marat Gordiev
- Tatarstan Regional Clinical Cancer Center, Kazan, Tatarstan, Russia
| | - Paul F. Engstrom
- Division of Medical Oncology, Extramural Research Program, Fox Chase Cancer Center, Philadelphia, PA, USA
| | - Rustem Khasanov
- Tatarstan Regional Clinical Cancer Center, Kazan, Tatarstan, Russia
| | - Anton Moroshek
- Tatarstan Regional Clinical Cancer Center, Kazan, Tatarstan, Russia
| | - Rustem Sitdikov
- Tatarstan Regional Clinical Cancer Center, Kazan, Tatarstan, Russia
| | | | - Robert A. Schnoll
- Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, USA,Corresponding Author: Robert A. Schnoll, Ph.D., Department of Psychiatry, University of Pennsylvania, 3535 Market Street, 4 Floor, Philadelphia, PA, 19104; Telephone: 215-746-7143; Fax: 215-746-7140;
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Association of genetic polymorphisms with personality profile in individuals without psychiatric disorders. Prog Neuropsychopharmacol Biol Psychiatry 2012; 39:40-6. [PMID: 22542868 DOI: 10.1016/j.pnpbp.2012.04.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 04/10/2012] [Accepted: 04/10/2012] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Population-based twin studies demonstrate that approximately 40-50% of the variability in personality dimensions results from genetic factors. This study assessed selected polymorphisms in the COMT Val158Met, MAOA 3'VNTR, 5HTTLPR, 102T/C 5-HT2A, DAT 3'VNTR and DRD2 exon 8 genes and evaluated their association with personality profiles, anxiety levels, and depressiveness in healthy subjects. METHODS This study included 406 unrelated (mean age 38.51 years), mentally and somatically healthy Caucasian subjects of Polish origin. The prevalence of the gene variants mentioned above and their association with personality profiles, anxiety levels, and depressiveness was assessed using the Temperament and Character Inventory, NEO Five-Factor Inventory, Spielberger's State-Trait Anxiety Inventory and Beck's Depression Inventory. RESULTS The effects of the 5HTTLPR gene on the s/s genotype and empathy (C2) were lowest in the entire group. The effects of gender, age and the HT2A gene for the T/T genotype and attachment (RD3) were highest in women. The effects of gender, age and the DAT gene on the 9/9 DAT genotype, compassion (C4) and cooperativeness (C) were lowest in women. The effects of gender, age and the COMT gene on the Met/Met genotype and neuroticism (NEU) NEO-FFI were also lowest in women. CONCLUSIONS Our results suggest considerable influence of individual genes on the formation of personality traits.
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Association between temperament in terms of the Regulative Theory of Temperament and DRD4 and DAT1 gene polymorphisms. Compr Psychiatry 2012; 53:789-96. [PMID: 22342155 DOI: 10.1016/j.comppsych.2012.01.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2011] [Revised: 01/10/2012] [Accepted: 01/11/2012] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVES This is a study of the association between DRD4 exon III VNTR and DAT1 3'-untranslated region polymorphisms on the one hand and temperament assessed with the Formal Characteristics of Behaviour-Temperament Inventory on the other hand. METHODS The study was run on 418 participants (314 women and 104 men) aged 18 to 55 years sampled from healthy male and female volunteers recruited from inhabitants of the Warsaw metropolis. RESULTS Main effects of sex were found for briskness (F(1,417) = 9.05, P = .003, η(2) = 0.022), perseveration (F(1,417) = 37.83, P < .001, η(2) = 0.085), sensory sensitivity (F(1,417) = 14.16, P < .001, η(2) = 0.003), and emotional reactivity (F(1,417) = 34.67, P < .001, η(2) = 0.078). A significant main effect of DAT1 variant was also found for sensory sensitivity (F(1,417) = 7.36, P = .007, η(2) = 0.018). No main effects of DRD4 on any of the analyzed temperament traits were found. A significant interaction of sex and DRD4 variant was found for sensory sensitivity (F(1,417) = 5.68, P = .018, η(2) = 0.014). No significant 3-way interactions (DAT1 × DRD4 × sex) were found. CONCLUSIONS A significant main effect of DAT1 polymorphism on sensory sensitivity and a significant interactive sex/DRD4 effect on that same trait were found.
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Abstract
The high prevalence of substance abuse in individuals with bulimia nervosa (BN) and the pervasive symptom substitution in many types of drug addiction suggest that a number of substances--including food--can impair an individual's self-control, even in the presence of negative consequences. Nonetheless, the neurobiological similarities between BN and drug addiction are not clearly established. This review explores how the specific eating patterns seen in BN (binge eating and purging, with intermittent dietary restriction) are particularly addictive and differentiate BN from other eating disorders and obesity. A number of peripheral and central biological aberrations seen in BN may result in altered reward sensitivity in these individuals, particularly through effects on the dopaminergic system. Neurobiological findings support the notion that BN is an addictive disorder, which has treatment implications for therapy and pharmacological manipulations.
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Abstract
Cigarette smoking is the main preventable cause of death in developed countries, and the development of more effective treatments is necessary. Cumulating evidence suggests that cognitive enhancement may contribute to the addictive actions of nicotine. Several studies have demonstrated that nicotine enhances cognitive performance in both smokers and non-smokers. Genetic studies support the role of both dopamine (DA) and nicotinic acetylcholine receptors (nAChRs) associated with nicotine-induced cognitive enhancement. Based on knockout mice studies, beta2 nAChRs are thought to be essential in mediating the cognitive effects of nicotine. alpha7nAChRs are associated with attentional and sensory filtering response, especially in schizophrenic individuals. Genetic variation in D2 type DA receptors and the catechol-O-methyltransferase enzyme appears to moderate cognitive deficits induced by smoking abstinence. Serotonin transporter (5-HTT) gene variation also moderates nicotine-induced improvement in spatial working memory. Less is known about the contribution of genetic variation in DA transporter and D4 type DA receptor genetic variation on the cognitive effects of nicotine. Future research will provide a clearer understanding of the mechanism underlying the cognitive-enhancing actions of nicotine.
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Affiliation(s)
- Aryeh I Herman
- Department of Psychiatry and VA Connecticut Healthcare System, School of Medicine, Yale University, West Haven, CT 06516, USA
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Schosser A, Fuchs K, Scharl T, Schloegelhofer M, Kindler J, Mossaheb N, Kaufmann RM, Leisch F, Kasper S, Sieghart W, Aschauer HN. Interaction between serotonin 5-HT2A receptor gene and dopamine transporter (DAT1) gene polymorphisms influences personality trait of persistence in Austrian Caucasians. World J Biol Psychiatry 2010; 11:417-24. [PMID: 20218802 DOI: 10.3109/15622970801935586] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We examined 89 normal volunteers using Cloninger's Temperament and Character Inventory (TCI). Genotyping the 102T/C polymorphism of the serotonin 5HT2A receptor gene and the ser9gly polymorphism in exon 1 of the dopamine D3 receptor (DRD3) gene was performed using PCR-RFLP, whereas the dopamine transporter (DAT1) gene variable number of tandem repeats (VNTR) polymorphism was investigated using PCR amplification followed by electrophoresis in an 8% acrylamide gel with a set of size markers. We found a nominally significant association between gender and harm avoidance (P=0.017; women showing higher scores). There was no association of either DAT1, DRD3 or 5HT2A alleles or genotypes with any dimension of the TCI applying Kruskal-Wallis rank-sum tests. Comparing homozygote and heterozygote DAT1 genotypes, we found higher novelty seeking scores in homozygotes (P=0.054). We further found a nominally significant interaction between DAT1 and 5HT2A homo-/heterozygous gene variants (P=0.0071; DAT1 and 5HT2A genotypes P value of 0.05), performing multivariate analysis of variance (MANOVA). Examining the temperamental TCI subscales, this interaction was associated with persistence (genotypes: P=0.004; homo-/heterozygous gene variants: P=0.0004). We conclude that an interaction between DAT1 and 5HT2A genes might influence the temperamental personality trait persistence.
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Affiliation(s)
- Alexandra Schosser
- Division of Biological Psychiatry, Department of Psychiatry & Psychotherapy, Medical University Vienna, Vienna, Austria.
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Osinsky R, Alexander N, Schmitz A, Kuepper Y, Müller E, Beer L, Koeppe L, Hennig J. Genetic Influences on Implicit Measures of Personality. JOURNAL OF INDIVIDUAL DIFFERENCES 2010. [DOI: 10.1027/1614-0001/a000007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Previous research has revealed various relationships between self-reported personality traits and specific variations in genes influencing serotonergic and dopaminergic pathways. In recent studies, however, personality was repeatedly assessed by the use of more indirect measures, such as the implicit association test (IAT). This tool is assumed to access automatic associations, reflecting the sum of former dispositional behavior and experience. The present study aimed to identify potential genetic effects on personality-related associations measured by the IAT. In a sample of 96 women we found correlations between genetic variations of the serotonin and dopamine transporters (5-HTTLPR and DAT 3’-VNTR) and indirectly measured traits of anxiety and agentic extraversion. In detail, the 5-HTTLPR was linked to the anxiety IAT, whereas the DAT 3-’VNTR was associated with performance in the agentic-extraversion IAT. These findings point out genetic influences on personality-related associations and emphasize the usefulness of the IAT in research on the biological foundations of dispositions.
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Affiliation(s)
- Roman Osinsky
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Nina Alexander
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Anja Schmitz
- Developmental Genetic Epidemiology Section, NIMH Bethesda, MD, USA
| | - Yvonne Kuepper
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Eva Müller
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Laura Beer
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Lena Koeppe
- Department of Psychology, Justus Liebig University Gießen, Germany
| | - Jürgen Hennig
- Department of Psychology, Justus Liebig University Gießen, Germany
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Relationships between angry-impulsive personality traits and genetic polymorphisms of the dopamine transporter. Biol Psychiatry 2009; 66:717-21. [PMID: 19368898 DOI: 10.1016/j.biopsych.2009.03.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Revised: 02/04/2009] [Accepted: 03/04/2009] [Indexed: 11/22/2022]
Abstract
BACKGROUND The 9-repeat variable number tandem repeat allele of the dopamine transporter has recently been associated with borderline personality disorder (BPD) in depressed patients. METHODS We investigated the association between the 9-repeat allele of the dopamine transporter and angry-impulsive personality traits in a family study with 512 subjects on the molecular genetics of depression and personality. RESULTS Across the whole sample, the 9-repeat allele of the dopamine transporter was associated with angry-impulsive personality traits (p = .002). This association was stronger in subjects with no history of mood disorders or BPD (odds ratio [OR] = 4.85, p = .008) than in subjects with a history of mood disorders (OR = 1.73, p = .033). Angry-impulsive traits were also associated with lifetime mood disorder diagnoses and with BPD. CONCLUSIONS The associations reported in this article suggest that the 9-repeat allele of the dopamine transporter is associated with angry-impulsive personality traits, independent of any link to mood disorder or BPD. This could form the basis of a dopaminergic neurobiological model of angry-impulsive personality traits.
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Influences of polymorphic variants of DRD2 and SLC6A3 genes, and their combinations on smoking in Polish population. BMC MEDICAL GENETICS 2009; 10:92. [PMID: 19761593 PMCID: PMC2758863 DOI: 10.1186/1471-2350-10-92] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Accepted: 09/17/2009] [Indexed: 11/10/2022]
Abstract
BACKGROUND Polymorphisms in dopaminergic genes may influence cigarette smoking by their potential impact on dopamine reward pathway function. A1 allele of DRD2 gene is associated with a reduced dopamine D2 receptor density, and it has been hypothesised that A1 carriers are more vulnerable to smoking. In turn, the 9-repeat allele of dopamine transporter gene (SLC6A3) has been associated with a substantial reduction in dopamine transporter, what might result in the higher level of dopamine in the synaptic cleft, and thereby protective role of this allele from smoking. In the present study we investigated whether polymorphic variants of DRD2 and SLC6A3 genes and their combinations are associated with the smoking habit in the Polish population. METHODS Genotyping for TaqIA polymorphism of DRD2 and SLC6A3 VNTR polymorphism was performed in 150 ever-smokers and 158 never-smokers. The association between the smoking status and smoking phenotypes (related to the number of cigarettes smoked daily and age of starting regular smoking), and genotype/genotype combinations was expressed by ORs together with 95% CI. Alpha level of 0.05, with Bonferroni correction whenever appropriate, was used for statistical significance. RESULTS At the used alpha levels no association between DRD2 and SLC6A3 genotypes and smoking status was found. However, A1 allele carriers reported longer abstinence periods on quitting attempts than non-carriers (p = 0.049). The ORs for heavier smoking were 0.38 (0.17-0.88), p = 0.023, and 0.39 (0.17-0.88), p = 0.021 in carriers compared to non-carriers of A1 or *9 allele, respectively, and the OR for this smoking phenotype was 8.68 (2.47-30.46), p = 0.0005 for the A1-/9- genotype combination, relatively to the A1+/9+. Carriers of *9 allele of SLC6A3 had over twice a lower risk to start smoking before the age of 20 years compared to non-carriers (sex-adjusted OR = 0.44; 95% CI: 0.22-0.89; p = 0.0017), and subjects with A1-/9- genotype combination had a higher risk for staring regular smoking before the age of 20 years in comparison to subjects with A1+/9+ genotype combination (sex-adjusted OR = 3.79; 95% CI:1.03-13.90; p = 0.003). CONCLUSION Polymorphic variants of DRD2 and SLC6A3 genes may influence some aspects of the smoking behavior, including age of starting regular smoking, the level of cigarette consumption, and periods of abstinence. Further large sample studies are needed to verify this hypothesis.
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Abstract
We utilized a cohort of 828 treatment-seeking self-identified white cigarette smokers (50% female) to rank candidate gene single nucleotide polymorphisms (SNPs) associated with the Fagerström Test for Nicotine Dependence (FTND), a measure of nicotine dependence which assesses quantity of cigarettes smoked and time- and place-dependent characteristics of the respondent's smoking behavior. A total of 1123 SNPs at 55 autosomal candidate genes, nicotinic acetylcholine receptors and genes involved in dopaminergic function, were tested for association to baseline FTND scores adjusted for age, depression, education, sex, and study site. SNP P-values were adjusted for the number of transmission models, the number of SNPs tested per candidate gene, and their intragenic correlation. DRD2, SLC6A3, and NR4A2 SNPs with adjusted P-values <0.10 were considered sufficiently noteworthy to justify further genetic, bioinformatic, and literature analyses. Each independent signal among the top-ranked SNPs accounted for approximately 1% of the FTND variance in this sample. The DRD2 SNP appears to represent a novel association with nicotine dependence. The SLC6A3 SNPs have previously been shown to be associated with SLC6A3 transcription or dopamine transporter density in vitro, in vivo, and ex vivo. Analysis of SLC6A3 and NR4A2 SNPs identified a statistically significant gene-gene interaction (P=0.001), consistent with in vitro evidence that the NR4A2 protein product (NURR1) regulates SLC6A3 transcription. A community cohort of N=175 multiplex ever-smoking pedigrees (N=423 ever smokers) provided nominal evidence for association with the FTND at these top ranked SNPs, uncorrected for multiple comparisons.
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25
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Schmid B, Blomeyer D, Becker K, Treutlein J, Zimmermann US, Buchmann AF, Schmidt MH, Esser G, Banaschewski T, Rietschel M, Laucht M. The interaction between the dopamine transporter gene and age at onset in relation to tobacco and alcohol use among 19-year-olds. Addict Biol 2009; 14:489-99. [PMID: 19740369 DOI: 10.1111/j.1369-1600.2009.00171.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent evidence suggests that heterogeneity in the age at onset could explain the inconsistent findings of association studies relating the dopamine transporter (DAT1) gene with alcohol and nicotine consumption. The aim of this study was to examine interactions between two DAT1 polymorphisms and different initiation ages with regard to alcohol and tobacco consumption levels and dependence. Two hundred and ninety-one young adults (135 males, 156 females) participating in the Mannheim Study of Children at Risk were genotyped for the 40-bp variable number of tandem repeats (VNTR) and rs27072 polymorphisms of DAT1. Age at initiation was assessed at age 15 and 19 years. Information about current alcohol and tobacco consumption was obtained at age 19 years using self-report measures and structured interviews. Results suggest that age at onset of intensive consumption moderated the association of the DAT1 gene with early adult substance use and dependence, revealing a DAT1 effect only among individuals homozygous for the 10r allele of the 40-bp VNTR who had started daily smoking or being intoxicated early in life. Equally, carriers of the T allele of the rs27072 polymorphism reporting an early age at first intoxication showed higher current alcohol consumption at age 19 years. In contrast, no interaction between rs27072 and the age at first cigarette with regard to later smoking was observed. These findings provide evidence that the DAT1 gene interacts with an early heavy or regular drug exposure of the maturing adolescent brain to predict substance (ab)use in young adulthood. Further studies are required to confirm these findings.
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Affiliation(s)
- Brigitte Schmid
- Department of Child and Adolescent Psychiatry and Psychotherapy, Central Institute of Mental Health, Mannheim, Germany
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Yacubian J, Büchel C. The genetic basis of individual differences in reward processing and the link to addictive behavior and social cognition. Neuroscience 2009; 164:55-71. [PMID: 19446009 DOI: 10.1016/j.neuroscience.2009.05.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Revised: 04/20/2009] [Accepted: 05/06/2009] [Indexed: 11/17/2022]
Abstract
Dopaminergic neurotransmission is widely recognized to be critical to the neurobiology of reward, motivation and addiction. Interestingly, social interactions and related behavior also activate the same neuronal system. Consequently, genetic variations of dopamine neurotransmission are thought influence reward processing that in turn may affect distinctive social behavior and susceptibility to addiction. This review focuses on advances made to date in an effort to link genetic individual variations and reward processing as a possible basis for addictive behaviors.
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Affiliation(s)
- J Yacubian
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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The biology of binge eating. Appetite 2009; 52:545-553. [PMID: 19501749 DOI: 10.1016/j.appet.2009.03.005] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 01/15/2009] [Accepted: 03/12/2009] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To examine the literature on binge eating to gain a better understanding of its biological foundations and their role in eating disorders. METHOD Literature review and synthesis. RESULTS Research using animal models has revealed several factors that contribute to the development and maintenance of binge eating. These factors, including stress, food restriction, the presence of palatable foods, and environmental conditioning, parallel many of the precursory circumstances leading to binge eating in individuals with bulimia nervosa and binge eating disorder. DISCUSSION The animal literature has opened a new avenue to aid in the understanding of the neurobiological basis of binge eating. Future endeavors examining the genetic and environmental correlates of binge eating behavior will further contribute to the understanding of the biological foundations of binge eating and assist with establishing diagnostic criteria and the development of novel treatments for eating disorders marked by binge eating.
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Styn MA, Nukui T, Romkes M, Perkins K, Land SR, Weissfeld JL. The impact of genetic variation in DRD2 and SLC6A3 on smoking cessation in a cohort of participants 1 year after enrollment in a lung cancer screening study. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:254-61. [PMID: 18563706 PMCID: PMC2730224 DOI: 10.1002/ajmg.b.30801] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Smoking cessation strategies continue to have disappointing results. By determining the interindividual genetic differences that influence smoking behaviors, we may be able to develop tailored strategies that increase the likelihood of successful cessation. This study attempts to determine genetic influences on the relationship between the dopamine pathway and smoking cessation by examining associations with a variable number tandem repeat variation in SLC6A3 and the DRD2 variants TaqIA (A2 vs. A1), TaqIB (B2 vs. B1), C957T (C vs. T), and -141C Ins/Del (C vs. Del). Baseline smokers in the Pittsburgh Lung Screening Study who provided information on smoking status 1 year later were evaluated. We frequency-matched those who were not abstinent at 1 year to those who were abstinent at 1 year by gender, decade of age, and time of enrollment (3-month intervals) in a 3:1 ratio (N = 881). Logistic regression was used to identify the effect of genotype on abstinence at 1 year. In a model containing the matching variables and other genotypes, DRD2 TaqIA was significantly associated with being abstinent at 1 year (P = 0.01). Compared to participants who were homozygous for the TaqIA major allele (A2A2), participants who carried at least one minor allele (A1) were less likely to quit (Odds Ratio: 0.47, 95% CI: 0.24-0.94). The other dopamine receptor genotypes and the SLC6A3 genotype were not associated with smoking status at 1 year. The association between DRD2 TaqIA and smoking cessation supports the hypothesis that genetic variation in the dopamine pathway influences smoking cessation.
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Affiliation(s)
- Mindi A. Styn
- University of Pittsburgh School of Nursing, Department of Health and Community Systems
| | - Tomoko Nukui
- University of Pittsburgh School of Medicine, Department of Medicine
| | - Marjorie Romkes
- University of Pittsburgh School of Medicine, Department of Medicine
| | - Kenneth Perkins
- University of Pittsburgh School of Medicine, Department of Psychiatry
| | - Stephanie R. Land
- University of Pittsburgh Graduate School of Public Health, Department of Biostatistics
| | - Joel L. Weissfeld
- University of Pittsburgh Graduate School of Public Health, Department of Epidemiology
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David SP, Munafò MR. Genetic variation in the dopamine pathway and smoking cessation. Pharmacogenomics 2009; 9:1307-21. [PMID: 18781857 DOI: 10.2217/14622416.9.9.1307] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Twin and family studies have established that genetic factors account for much of the variation in tobacco dependence. Therefore, identification of genetic variants predictive of successful smoking cessation has implications for the future prospect of personalized smoking cessation therapies. Converging data implicate the dopamine pathway as an important neural substrate for tobacco dependence. Several candidate genes within the dopamine pathway (e.g., DRD2 and COMT) have been reported to be associated with the efficacy of bupropion and nicotine replacement therapy, and others (e.g., SLC6A3 and DRD4) have been reported to be associated with smoking cessation independent of pharmacotherapy. However, few of these candidate genes are present within regions of suggestive or significant linkage or overlap with genome-wide linkage or association studies of tobacco dependence or smoking cessation. Future studies should seek to replicate genome-wide association analyses with individual-level genotyping, and use better-defined smoking cessation phenotypes. Once robust evidence for association is established, which may take several more years, further research into the likely cost-effectiveness, feasibility and acceptability of personalized medicine for smoking cessation will be necessary before it can be translated into practice.
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Affiliation(s)
- Sean P David
- Brown University Center for Primary Care and Prevention, Department of Family Medicine, The Warren Alpert Medical School of Brown University, Memorial Hospital of Rhode Island, Pawtucket, RI 02860, USA
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Triche EW, Hossain N, Paidas MJ. Genetic influences on smoking cessation and relapse in pregnant women. J OBSTET GYNAECOL 2008; 28:155-60. [PMID: 18393009 DOI: 10.1080/01443610801912725] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cigarette smoking during pregnancy continues to be a significant public health concern. Maternal smoking during pregnancy has been associated with low birth weight (<2500 g), fetal growth restriction, placental problems, pre-term delivery and spontaneous abortion. Mothers who smoke during pregnancy are twice as likely to give birth to low birth weight infants, and smoking during pregnancy is estimated to be responsible for 20-30% of all low birth weight infants. Smoking during pregnancy not only affects placental function, thus causing obstetrical complications, but nicotine also crosses the placenta and acts as a neuroteratogen. This in turn, elevates the risk of cognitive and auditory processing deficits, and has also been found to be negatively associated with long-term consequences on offspring behaviour. In addition, smoking has negative long-term health consequences for both mother and child, including respiratory conditions, cancer and cardiovascular problems. This review provides insight into the genetic influences on smoking behaviour in pregnant women. In particular, the roles of genes in the neurotransmitter pathways are highlighted. It also emphasises the need for further research in this area, and provides rationale for the importance of focusing on pregnant women who are highly motivated to quit when researching smoking behaviours in women.
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Affiliation(s)
- E W Triche
- Yale University School of Medicine, New Haven, CT, USA
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Abstract
AIMS Attempts to further our understanding of the determinants of cigarette smoking, tobacco addiction and related behaviours have included the dissection of genetic influences on these phenotypes. This review summarizes the current state of evidence from both twin and adoption studies and molecular genetic studies. We also review future research horizons and the direction which studies of this kind are likely to take in the near future. FINDINGS There is consistent evidence from twin and adoption studies that genetic factors play a role in the aetiology of cigarette smoking. Nevertheless, despite a large number of candidate gene studies, and a smaller number of linkage studies, few reported associations and chromosomal regions of interest have proved to replicate reliably. This is due most probably to the small effects of individual loci on complex behaviours such as smoking. CONCLUSIONS Future research is likely to include the study of gene x environment interactions (including gene x treatment interactions, which offer the prospect of genetically tailored smoking cessation treatment) and the use of more sophisticated smoking-related phenotypes, such as longitudinal smoking trajectories, and intermediate phenotypes which use technologies such as neuroimaging and other laboratory and biobehavioural measures.
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Affiliation(s)
- Marcus R Munafò
- Department of Experimental Psychology, University of Bristol, Bristol, UK.
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Hünnerkopf R, Strobel A, Gutknecht L, Brocke B, Lesch KP. Interaction between BDNF Val66Met and dopamine transporter gene variation influences anxiety-related traits. Neuropsychopharmacology 2007; 32:2552-60. [PMID: 17392738 DOI: 10.1038/sj.npp.1301383] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The involvement in neural plasticity and the mediation of effects of repeated stress exposure and long-term antidepressant treatment on hippocampal neurogenesis supports a critical role of brain-derived neurotrophic factor (BDNF) in the pathophysiology of affective and other stress-related disorders. A previously reported valine to methionine substitution at amino-acid position 66 (BDNF Val66Met) seems to account for memory disturbance and hippocampal dysfunction. In the present study, we evaluated the impact of the BDNF Val66Met polymorphism on individual differences in personality traits in a sample of healthy volunteers in relation to other common gene variants thought to be involved in the pathophysiology of affective disorders, such as the serotonin transporter promoter polymorphism (5-HTTLPR) and a variable number of tandem repeat polymorphism of the dopamine transporter gene (DAT VNTR). Personality traits were assessed using the NEO personality inventory (NEO-PI-R) and Tridimensional Personality Questionnaire (TPQ). There was a significant DAT VNTR-dependent association between NEO-PI-R Neuroticism and the BDNF Val66Met polymorphism. Among individuals with at least one copy of the DAT 9-repeat allele, carriers of the BDNF Met allele exhibited significantly lower Neuroticism scores than noncarriers. This interaction was also observed for TPQ Harm Avoidance, a personality dimension related to Neuroticism. Our results support the notion that allelic variation at the BDNF locus--in interaction with other gene variants--influences anxiety- and depression-related personality traits.
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Affiliation(s)
- Regina Hünnerkopf
- Molecular and Clinical Psychobiology, Department of Psychiatry and Psychotherapy, University of Würzburg, Würzburg, Germany
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Fernander AF, Shavers VL, Hammons GJ. A biopsychosocial approach to examining tobacco-related health disparities among racially classified social groups. Addiction 2007; 102 Suppl 2:43-57. [PMID: 17850613 DOI: 10.1111/j.1360-0443.2007.01954.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
AIMS To articulate a broader, multi-causal model that incorporates psychosocial and environmental factors that can differ systematically across racially classified social groups (RCSGs) and impact biological pathways related to the development of tobacco-related diseases. METHODS This paper is built upon a review of the existing scientific literature on selected biopsychosocial factors (diet/nutrition, obesity, alcoholic intake, psychosocial stress, occupational/environmental exposures and exposure to other diseases and illnesses) and tobacco use in examining the biological contributions to differences in tobacco-related health outcomes among RCSGs. FINDINGS Recent work has focused on RCSG genetic variations as a possible explanation for differences in tobacco-related health disparities. It is argued in this paper that, given the genetic heterogeneity 'within' RCSGs, it is unlikely that across RCSG genetic variations are likely to be the major source of differences impacting biological pathways in tobacco-related health outcomes. The evidence shows that results, even at the level of within-population genetic variations, have been limited and often inconsistent. A conceptual framework is proposed to account for biological pathways related to the development of tobacco-related diseases. CONCLUSIONS Determinants of tobacco-related health disparities are not understood clearly. The contribution of biological factors may be important. Current efforts to determine biological differences in tobacco use and related diseases among RCSGs have focused primarily on genetic variations. However, this approach has limitations. An alternative biopsychosocial framework that examines the potential biological mechanisms through which life experiences and behavior might affect tobacco use and health outcomes in these population groups is needed, including those of life-style (e.g. diet/nutrition, obesity, physical exercise, alcohol consumption), psychosocial (e.g. stress and coping), occupational/environmental exposures and the presence of other diseases/illnesses.
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Affiliation(s)
- Anita F Fernander
- Behavioral Science Department, College of Medicine, University of Kentucky, Lexington, KY, USA
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Dragan WŁ, Oniszczenko W. An association between dopamine D4 receptor and transporter gene polymorphisms and personality traits, assessed using NEO-FFI in a Polish female population. PERSONALITY AND INDIVIDUAL DIFFERENCES 2007. [DOI: 10.1016/j.paid.2007.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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David SP, Brown RA, Papandonatos GD, Kahler CW, Lloyd-Richardson EE, Munafò MR, Shields PG, Lerman C, Strong D, McCaffery J, Niaura R. Pharmacogenetic clinical trial of sustained-release bupropion for smoking cessation. Nicotine Tob Res 2007; 9:821-33. [PMID: 17654295 PMCID: PMC2039873 DOI: 10.1080/14622200701382033] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This randomized, double-blinded, placebo-controlled trial examined genetic influences on treatment response to sustained-release bupropion for smoking cessation. Smokers of European ancestry (N = 291), who were randomized to receive bupropion or placebo (12 weeks) plus counseling, were genotyped for the dopamine D2 receptor (DRD2-Taq1A), dopamine transporter (SLC6A3 3' VNTR), and cytochrome P450 2B6 (CYP2B6 1459 CT) polymorphisms. Main outcome measures were cotinine-verified point prevalence of abstinence at end of treatment and at 2-, 6-, and 12-month follow-ups post quit date. Using generalized estimating equations, we found that bupropion, compared with placebo, was associated with significantly greater odds of abstinence at all time points (all p values<.01). We found a significant DRD2 x bupropion interaction (B = 1.49, SE = 0.59, p = .012) [corrected] and a three-way DRD2 x bupropion x craving interaction on 6-month smoking cessation outcomes (B = -0.45, SE = 0.22, p = .038), such that smokers with the A2/A2 genotype demonstrated the greatest craving reduction and the highest abstinence rates with bupropion. Furthermore, there was a significant DRD2 x CYP2B6 interaction (B = 1.43, SE = 0.56, p = .01), such that individuals with the DRD2-Taq1 A2/A2 genotype demonstrated a higher odds of abstinence only if they possessed the CYP2B6 1459 T/T or C/T genotype. Because the sample size of this study was modest for pharmacogenetic investigations, the results should be interpreted with caution. Although these results require replication, the data suggest preliminarily that the DRD2-Taq1A polymorphism may influence treatment response to bupropion for smoking cessation and, further, that exploration of gene x gene and gene x craving interactions in future, larger studies may provide mechanistic insights into the complex pharmacodynamics of bupropion.
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Affiliation(s)
- Sean P David
- Brown University Center for Primary Care and Prevention, Providence, RI 02860, USA.
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Segman RH, Kanyas K, Karni O, Lerer E, Goltser-Dubner T, Pavlov V, Lerer B. Why do young women smoke? IV. Role of genetic variation in the dopamine transporter and lifetime traumatic experience. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:533-40. [PMID: 17427187 DOI: 10.1002/ajmg.b.30507] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cigarette smoking is a complex behavior to which environmental, psychological, and genetic factors contribute. Applying a multifactorial model, we examined the role of genetic variation in the dopamine transporter (DAT1) in smoking initiation (SI) and nicotine dependence. The participants were female college students who had never smoked (n = 148) or had smoked daily for at least a year (n = 242). All participants provided extensive background information and completed a series of psychological instruments. Five SNPs were genotyped in the 3' and 5' regions of DAT1. Data were analyzed by logistic regression. The best fitting model for SI (P = 1.9 x 10(-17), Nagelkerke R2 = 0.33) revealed novelty seeking (OR = 1.14, P = 0.000004) and lifetime traumatic experience (OR = 2.3, P = 0.001) as risk factors and a DAT1_E15 + 274-DAT1_VNTR G-9 haplotype as protective (OR = 0.57, P = 0.03). In the model for nicotine dependence (P = 1.4 x 10(-8), Nagelkerke R2 = 0.27) novelty seeking was a risk factor (OR = 1.07, P = 0.03); the DAT1_E15+274-DAT1_VNTR G-9 haplotype (OR = 0.37, P = 0.001) and the interaction between trauma and a DAT1_E15 + 274-DAT1_VNTR C-9 haplotype (OR = 0.15, P = 0.01) were protective. Lifetime experience of trauma was associated with high nicotine dependence among non-carriers of the C-9 haplotype but not among carriers of this haplotype. These findings indicate that in the context of a multifactorial model, haplotypes in the 3' region of DAT1 influence the propensity of young women to initiate smoking as well as the severity of nicotine dependence once the habit is established. A haplotype in the 3' untranslated region of DAT1 modifies the effect of lifetime traumatic experience on the severity of nicotine dependence.
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Affiliation(s)
- Ronnen H Segman
- Department of Psychiatry, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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Stapleton JA, Sutherland G, O'Gara C. Association between dopamine transporter genotypes and smoking cessation: a meta-analysis. Addict Biol 2007; 12:221-6. [PMID: 17508996 DOI: 10.1111/j.1369-1600.2007.00058.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This review assessed the evidence of an association between genotypes of the dopamine transporter (DAT1, SLC6A3) 3' untranslated region (3'UTR) variable number of tandem repeats (VNTR) and smoking cessation. Five studies (seven cohorts) comprising 2155 subjects were included in the meta-analysis. All gave data on the number of smokers who had stopped smoking and the number still smoking for those with one or more variant 9-repeat alleles and other genotypes. Three studies (comprising five cohorts) were cross-sectional population surveys and two were smoking cessation treatment programs with follow-up. Four of the five studies (six of the seven cohorts) showed a trend in favor of cessation when the variant 9-repeat allele was present, although only one study showed a statistically significant effect. The pooled odds ratio in favor of a greater likelihood of cessation for the variant 9-repeat allele was 1.15 [95% confidence interval (CI) = 0.97-1.37]. In a more refined analysis where cohorts within studies were treated as separate samples and adjusted odds ratios were used, the overall pooled odds ratio in favor of cessation with the 9-repeat alleles was 1.20 (95% CI = 1.01-1.43). These results support the hypothesis that the DAT1 3'UTR VNTR polymorphism is associated with smoking cessation. One or more variant 9-repeat alleles relative to the more common 10-repeat allele confers a greater likelihood of cessation, indicative of lower dependence on tobacco. The effect was a 20% increase in the odds of cessation for those with a variant allele.
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Affiliation(s)
- John A Stapleton
- Tobacco Research Group, Department of Psychological Medicine, Kings College London, Institute of Psychiatry, London, UK.
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O'Gara C, Stapleton J, Sutherland G, Guindalini C, Neale B, Breen G, Ball D. Dopamine transporter polymorphisms are associated with short-term response to smoking cessation treatment. Pharmacogenet Genomics 2007; 17:61-7. [PMID: 17264803 DOI: 10.1097/01.fpc.0000236328.18928.4c] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To examine the association between polymorphisms in the dopamine transporter gene (SLC6A3, DAT1) and treatment outcome in smokers attempting to quit using either nicotine replacement therapy or bupropion. METHODS The sample consisted of 583 smokers recruited from a smoking cessation clinic, and followed throughout the 4 weeks of post-cessation treatment with behavioural support and either nicotine replacement therapy or bupropion. RESULTS At 1 week after smoking cessation, the 3' untranslated region (3'UTR) variable number of tandem repeats (VNTRs) and the 30-bp intron 8 VNTR DAT1 genotypes were associated with the ability to stop smoking (3'UTR VNTR, odds ratio=2.0, 95% confidence interval=1.2-3.5, novel intron 8 VNTR, odds ratio=1.8, 95% confidence interval=1.0-2.9), controlling for potential confounders. The results were weaker and no longer significant at a 4-week follow-up. CONCLUSIONS We find evidence, although modest, of a medium-sized effect of DAT1 genotype on the ability to stop smoking early in a smoking cessation attempt. If the effect is real, and is strongest in the very early stages of smoking cessation, this suggests that the primary utility of DAT1 screening in this field will be in the identification of those most at risk of early relapse after quitting.
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Affiliation(s)
- Colin O'Gara
- Tobacco Research Group, Department of Psychological Medicine bNational Addiction Centre, King's College London, Institute of Psychiatry, London, UK.
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Ton TGN, Rossing MA, Bowen DJ, Srinouanprachan S, Wicklund K, Farin FM. Genetic polymorphisms in dopamine-related genes and smoking cessation in women: a prospective cohort study. Behav Brain Funct 2007; 3:22. [PMID: 17466074 PMCID: PMC1865548 DOI: 10.1186/1744-9081-3-22] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Accepted: 04/28/2007] [Indexed: 11/24/2022] Open
Abstract
Background Genes involved in dopaminergic neurotransmission have been suggested as candidates for involvement in smoking behavior. We hypothesized that alleles associated with reduced dopaminergic neurotransmission would be more common in continuing smokers than among women who quit smoking. Methods The study included 593 women aged 26–65 years who participated in a twelve month smoking cessation trial conducted in 1993–1994. Participants were contacted three years after the trial to obtain updated smoking history and biological specimens. Seven polymorphisms were assessed in genes involved in dopamine synthesis (tyrosine hydoxylase [TH]), receptor activation (dopamine receptors [DRD2, DRD3, DRD4]), reuptake (dopamine transporter [SLC6A3]), and metabolism (catechol-o-methyltransferase [COMT]). Smoking cessation was assessed as "short-term" quitting (abstinence for the seven days before the conclusion of the trial) and "long-term" quitting (abstinence for the six months before a subsequent interview conducted several years later). Results We observed no association of any polymorphism with either short- or long-term quitting. Although some relative risk estimates were consistent with weak associations, either the direction of effect was opposite of that hypothesized, or results of the short- and long-term cessation endpoints differed. However, effect modification on smoking cessation was observed between DRD2 Taq1A and SLC6A3 VNTR polymorphisms, DRD3 Ser/Gly and d,1-fenfluramine, and DRD4 VNTR and d,1-fenfluramine. Conclusion Although these results fail to support prior findings of independent associations of these polymorphisms with smoking status, our exploratory findings suggestive of gene-gene and gene-treatment interactions warrants further investigation.
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Affiliation(s)
- Thanh GN Ton
- Department of Neurology, University of Washington, Box 359775, 325 Ninth Ave, Suite 3EH70, 98195-9775 Seattle, WA, USA
- Department of Epidemiology, University of Washington, Box 357236, 98195-7236 Seattle, WA, USA
| | - Mary Anne Rossing
- Department of Neurology, University of Washington, Box 359775, 325 Ninth Ave, Suite 3EH70, 98195-9775 Seattle, WA, USA
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, PO Box 19024, 98109-1024 Seattle, WA, USA
| | - Deborah J Bowen
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, PO Box 19024, 98109-1024 Seattle, WA, USA
| | - Sengkeo Srinouanprachan
- Center for Ecogenetics and Environmental Health, University of Washington, 4225 Roosevelt Way NE, Suite 100, 98105-6099 Seattle, WA, USA
| | - Kristine Wicklund
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, PO Box 19024, 98109-1024 Seattle, WA, USA
| | - Federico M Farin
- Center for Ecogenetics and Environmental Health, University of Washington, 4225 Roosevelt Way NE, Suite 100, 98105-6099 Seattle, WA, USA
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Abstract
Solute carrier 6 (SLC6) is a gene family of ion-coupled plasma membrane cotransporters, including transporters of neurotransmitters, amino acids, and osmolytes that mediate the movement of their substrates into cells to facilitate or regulate synaptic transmission, neurotransmitter recycling, metabolic function, and fluid homeostasis. Polymorphisms in transporter genes may influence expression and activity of transporters and contribute to behavior, traits, and disease. Determining the relationship between the monoamine transporters and complex psychiatric disorders has been a particular challenge that is being met by evolving approaches. Elucidating the functional consequences of and interactions among polymorphic sites is advancing our understanding of this relationship. Examining the influence of environmental influences, especially early-life events, has helped bridge the gap between genotype and phenotype. Refining phenotypes, through assessment of endophenotypes, specific behavioral tasks, medication response, and brain network properties has also improved detection of the impact of genetic variation on complex behavior and disease.
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Affiliation(s)
- Maureen K Hahn
- Department of Pharmacology and Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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41
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Guo S, Chen DF, Zhou DF, Sun HQ, Wu GY, Haile CN, Kosten TA, Kosten TR, Zhang XY. Association of functional catechol O-methyl transferase (COMT) Val108Met polymorphism with smoking severity and age of smoking initiation in Chinese male smokers. Psychopharmacology (Berl) 2007; 190:449-56. [PMID: 17206495 DOI: 10.1007/s00213-006-0628-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Accepted: 10/25/2006] [Indexed: 12/16/2022]
Abstract
RATIONALE Catechol-O-methyltransferase (COMT) is an enzyme involved in the degradation and inactivation of the neurotransmitter dopamine, which is important in mediating drug reward such as nicotine in tobacco smoke. Different COMT alleles encode enzyme whose activity varies from three- to fourfold that may affect dopamine levels and alter subjective effects of nicotine. Recent evidence also suggests that a COMT polymorphism may be especially important in determining an individual's predisposition to developing nicotine dependence. SUBJECTS AND METHODS We studied the COMT Val108Met polymorphism in a male population of 203 current smokers, 66 former smokers, and 102 non-smokers. The age-adjusted odds ratios were estimated by multiple logistic regression models. RESULTS The results showed no significant association of the COMT Val108Met with initiation, persistent smoking, or smoking cessation. However, current smokers with the Met allele had significantly higher Fagerstrom Test for Nicotine Dependence scores (7.5 +/- 2.1 vs 6.8 +/- 1.8, p = 0.018) and started smoking significantly earlier (18.4 +/- 4.9 vs 20.1 +/- 5.9 years, p = 0.036). CONCLUSIONS These results suggest that the COMT Val108Met polymorphism may not influence smoking status in a Chinese male population but may influence the age at which smoking started and smoking severity among smokers. However, the findings must be regarded as preliminary because of the relatively small sample size and marginal associations and should be replicated in a larger cohort.
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Affiliation(s)
- Song Guo
- Institute of Mental Health, Peking University, Beijing, 100083, China
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Ho MK, Tyndale RF. Overview of the pharmacogenomics of cigarette smoking. THE PHARMACOGENOMICS JOURNAL 2007; 7:81-98. [PMID: 17224913 DOI: 10.1038/sj.tpj.6500436] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cigarette smoking increases the risk of numerous health problems, including cancer, cardiovascular and pulmonary disorders, making smoking the leading cause of preventable death in the world. Nicotine is primarily responsible for the highly addictive properties of cigarettes. Although the majority of smokers express a desire to quit, few are successful in doing so. Twin and family studies have indicated substantial genetic contributions to smoking behaviors. One major research focus has been to elucidate the specific genes involved; this has been accomplished primarily through genome-wide linkage analyses and candidate gene association studies. Much attention has focused on genes involved in the neurotransmitter pathways for the brain reward system and genes altering nicotine metabolism. This paper reviews the current state of knowledge for genetic factors implicated in smoking behaviors, and examines how genetic variations may affect therapeutic outcomes for drugs used to assist smoking cessation.
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Affiliation(s)
- M K Ho
- Centre for Addiction and Mental Health, Department of Pharmacology, University of Toronto, Toronto, Canada
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Kim SJ, Kim YS, Kim CH, Lee HS. Lack of association between polymorphisms of the dopamine receptor D4 and dopamine transporter genes and personality traits in a Korean population. Yonsei Med J 2006; 47:787-92. [PMID: 17191306 PMCID: PMC2687817 DOI: 10.3349/ymj.2006.47.6.787] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Human personality traits have a considerable genetic component. Cloninger et al. were the first to postulate that certain personality traits, such as novelty seeking, are related to the dopamine neurotransmitter system. In this study, we investigated the associations between dopamine receptor D4 (DRD4) exon III and dopamine transporter (DAT1) polymorphisms and personality traits. The DRD4 and DAT1 gene polymorphisms were genotyped in 214 healthy Korean subjects, whose personality traits were assessed with the Temperament and Character Inventory (TCI). There were no significant differences between scores of TCI temperament dimensions (novelty seeking, harm avoidance, reward dependence, and persistence) and DRD4 gene polymorphism. The DAT1 gene polymorphisms also showed no significant association with any of the temperament subscales of the TCI. These data suggest that DRD4 and DAT1 gene polymorphism may not associated with personality traits in a Korean population.
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Affiliation(s)
- Se Joo Kim
- Department of Psychiatry and Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Young Shin Kim
- Child Study Center, Yale University School of Medicine, New Heaven, CT, USA
| | - Chan-Hyung Kim
- Department of Psychiatry and Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Hong Shick Lee
- Department of Psychiatry and Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Korea
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Cevoli S, Mochi M, Scapoli C, Marzocchi N, Pierangeli G, Pini LA, Cortelli P, Montagna P. A genetic association study of dopamine metabolism-related genes and chronic headache with drug abuse. Eur J Neurol 2006; 13:1009-13. [PMID: 16930369 DOI: 10.1111/j.1468-1331.2006.01415.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To assess the role of dopamine metabolism-related genes in the genetic liability to chronic headache with drug abuse (DA). We performed a genetic association study using four functional polymorphisms of the dopamine receptor 4 (DRD4), dopamine transporter (DAT), mono-amino-oxidase A (MAOA) and cathecol-O-methyl-transferase (COMT) genes in 103 patients with chronic daily headache associated with DA (CDHDA). Control samples were 117 individuals without headache or DA (controls) and 101 patients with episodic migraine without aura and without DA (MO). No differences were found at the COMT and MAOA genes among the three groups investigated. Allele 4 of DRD4 was significantly overrepresented in patients with MO compared with both controls and CDHDA. Allele 10 of the DAT gene was significantly underrepresented in patients with CDHDA when compared with the MO group. Genetic variability at the DRD4 gene is involved in the predisposition to episodic MO but not to DA, while liability to CDHDA may involve genetic variability at the DAT gene in comparison with episodic MO.
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Affiliation(s)
- S Cevoli
- Department of Neurological Sciences, University of Bologna Medical School, Bologna, Italy
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45
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Timberlake DS, Haberstick BC, Lessem JM, Smolen A, Ehringer M, Hewitt JK, Hopfer C. An association between the DAT1 polymorphism and smoking behavior in young adults from the National Longitudinal Study of Adolescent Health. Health Psychol 2006; 25:190-7. [PMID: 16569110 DOI: 10.1037/0278-6133.25.2.190] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Associations between smoking behavior and polymorphisms in the dopaminergic genes (DAT1 and DRD2) were tested by using within- and between-family measures of allelic transmission in 2,448 young adults from the National Longitudinal Study of Adolescent Health. The 9-repeat allele of the dopamine transporter gene polymorphism (DAT1) was inversely associated with smoking in samples that included all subjects and only those who had initiated smoking, accounting for approximately 1% of the variance. Never smokers and current nonsmokers had an excess transmission of the 9-repeat allele compared with regular smokers, suggesting a protective effect of the 9-repeat allele, which is hypothesized to alter synaptic dopamine levels.
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Affiliation(s)
- David S Timberlake
- Institute for Behavioral Genetics, University of Colorado at Boulder, Boulder, CO 80309-0447, USA.
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Brody AL, Mandelkern MA, Olmstead RE, Scheibal D, Hahn E, Shiraga S, Zamora-Paja E, Farahi J, Saxena S, London ED, McCracken JT. Gene variants of brain dopamine pathways and smoking-induced dopamine release in the ventral caudate/nucleus accumbens. ACTA ACUST UNITED AC 2006; 63:808-16. [PMID: 16818870 PMCID: PMC2873693 DOI: 10.1001/archpsyc.63.7.808] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Preclinical studies demonstrate that nicotine administration leads to dopamine release in the ventral striatum. However, human studies reveal considerable interindividual variability in the extent of smoking-induced dopamine release. OBJECTIVE To determine whether common gene variants of the brain dopamine pathway explain this observed phenotypic variability in humans. DESIGN Blood samples were drawn to determine gene variants of dopamine system components, and positron emission tomography scanning with the radiotracer raclopride labeled with radioactive carbon (11C) was performed to measure smoking-induced dopamine release. SETTING Academic brain imaging center. PARTICIPANTS Forty-five tobacco-dependent smokers. INTERVENTIONS Subjects either smoked a cigarette (n = 35) or did not smoke (n = 10) during positron emission tomography scanning. MAIN OUTCOME MEASURES Gene variants of dopamine system components (the dopamine transporter variable nucleotide tandem repeat, D2 receptor Taq A1/A2, D4 receptor variable nucleotide tandem repeat, and catechol-O-methyltransferase Val158Met polymorphisms) and change in [11C]raclopride binding potential in the ventral caudate/nucleus accumbens on positron emission tomography scans. RESULTS For subjects who smoked during scanning, those with at least one 9 allele of the dopamine transporter variable nucleotide tandem repeat, fewer than 7 repeats of the D4 variable nucleotide tandem repeat, and the Val/Val catechol-O-methyltransferase genotype had greater decreases in binding potential (an indirect measure of dopamine release) with smoking than those with the alternate genotypes. An overall decrease in ventral caudate/nucleus accumbens binding potential in those who smoked compared with those who did not smoke was also found but was smaller in magnitude than previously reported. CONCLUSIONS Smokers with genes associated with low resting dopamine tone have greater smoking-induced (phasic) dopamine release than those with alternate genotypes. These findings suggest that dopamine system genotype variabilities explain a significant proportion of the interindividual variability in smoking-induced dopamine release and indicate that smoking-induced dopamine release has a genetic predisposition.
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Affiliation(s)
- Arthur L Brody
- Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA 90095, USA.
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Lee AM, Tyndale RF. Drugs and genotypes: how pharmacogenetic information could improve smoking cessation treatment. J Psychopharmacol 2006; 20:7-14. [PMID: 16785264 DOI: 10.1177/1359786806066039] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Current smoking cessation treatments are not optimal as the long-term abstinence rates are low. Nicotine replacement therapy and bupropion are the only pharmacotherapies widely available to smokers and there is a need to improve current cessation treatments and to develop new drug therapies. Our goal is to use pharmacogenetic information to improve smoking cessation treatments. Candidate genes include those involved in central mechanisms (such as genes encoding the nicotinic acetylcholine receptors, dopamine receptors, dopamine transporters and opioid receptors) and peripheral mechanisms (such as genes encoding the drug-metabolizing enzymes CYP2A6 and CYP2B6). Pharmacogenetics could be used to improve current smoking cessation treatments through two general approaches. The first would be to identify novel drug targets based on genetic variants that are associated with a natural protection against nicotine dependence, decreased smoking behaviour and/or increased smoking cessation. This knowledge could be used to develop drugs that can mimic these advantages, reducing the risk for acquisition, block the rewarding effects of smoking, decreasing the amount smoked and increasing cessation. The second would be to identify smokers with particular genetic variants who are likely to respond better to one treatment (or dose) versus another and to individualize their treatment to maximize long-term abstinence. This review will highlight examples of how pharmacogenetic information from central and peripheral candidate genes could contribute to improving smoking cessation outcomes by these two approaches.
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Affiliation(s)
- Anna M Lee
- Centre for Addiction and Mental Health, Department of Pharmacology, University of Toronto, Toronto, Canada
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Kim SJ, Kim YS, Lee HS, Kim SY, Kim CH. An interaction between the serotonin transporter promoter region and dopamine transporter polymorphisms contributes to harm avoidance and reward dependence traits in normal healthy subjects. J Neural Transm (Vienna) 2006; 113:877-86. [PMID: 16604301 DOI: 10.1007/s00702-006-0444-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Accepted: 01/08/2006] [Indexed: 10/25/2022]
Abstract
There is evidence for an association between polymorphisms of serotonin- and dopamine-related genes and temperamental personality traits. Recent findings have shown that interactions between allelic variants of the different genes may contribute to personality traits. We examined the effects of serotonin transporter-linked promoter region (5-HTTLPR) and dopamine transporter (DAT1) gene polymorphisms for associations with the Temperament and Character Inventory (TCI) temperament subscales in 209 Koreans. We found that the variants of 5-HTTLPR interacted with the DAT1 gene polymorphism to influence the HA and RD temperament subscales of TCI. Neither of these two genes affected any subscales of TCI alone.Controlling for the effects of gender and age, we found significant interactions between 5-HTTLPR and DAT1 genes on Harm Avoidance (HA) and Reward Dependence (RD) as measured by the TCI (Hotelling's Trace = 3.0, P = 0.02). In the presence of the DAT1 10/10 genotype, subjects of group L of 5-HTTLPR had a significantly higher HA score and significantly lower RD score than those of group S (F = 5.04, df = 1, p = 0.03 and F = 8.35, df = 1, p = 0.004, respectively). These findings suggest that the variants of 5-HTTLPR interacted with the DAT1 gene polymorphism to influence the HA and RD temperament subscales of TCI.
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Affiliation(s)
- S J Kim
- Department of Psychiatry, Institute of Behavioral Science in Medicine, New Haven, CT, USA
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Abstract
Biogenic amine neurotransmitters are released from nerve terminals and activate pre- and postsynaptic receptors. Released neurotransmitters are sequestered by transporters into presynaptic neurons, a major mode of their inactivation in the brain. Genetic studies of human biogenic amine transporter genes, including the dopamine transporter (hDAT; SLC6A3), the serotonin transporter (hSERT; SLC6A4), and the norepinephrine transporter (hNET; SLC6A2) have provided insight into how genomic variations in these transporter genes influence pharmacology and brain physiology. Genetic variants can influence transporter function by various mechanisms, including substrate affinities, transport velocity, transporter expression levels (density), extracellular membrane expression, trafficking and turnover, and neurotransmitter release. It is increasingly apparent that genetic variants of monoamine transporters also contribute to individual differences in behavior and neuropsychiatric disorders. This chapter summarizes current knowledge of transporters with a focus on genomic variations, expression variations, pharmacology of protein variants, and known association with human diseases.
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Affiliation(s)
- Z Lin
- Department of Psychiatry, Harvard Medical School, Division of Neurochemistry, New England Primate Research Center, 1 Pine Hill Drive, Southborough, MA 01772-9102, USA
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Abstract
Smoking is a complex behavior influenced by environ-mental and genetic factors. A number of twin studies demonstrate genetic influences on multiple aspects of smoking including initiation, dependence, continuation, amount consumed, and cessation. It is likely that this genetic risk involves a complex interaction between multiple genes in different biologic pathways. These may include genes involved in the general aspect of dependence (eg, genes within the dopaminergic system) and those more specific to nicotine dependence (eg, genes encoding nicotinic acetylcholine receptors and nicotine-metabolizing enzymes). Genome-wide linkage analyses and gene association studies provide approaches for identifying these genes. This review provides a brief highlight of data from some of the candidate gene association studies and discusses some of the discrepancies found in the literature. In addition, the authors have reviewed some recent studies examining how genetic variations in drug-metabolizing enzymes and drug targets can influence the response to treatment with drugs such as bupropion and nicotine.These latter studies provide the potential for maximizing treatment efficacy by individualizing the type, dosage, and duration of the treatment based on an individual's genotype/phenotype. Significant advances have been made in understanding the genetic contribution to smoking behaviors. These and future studies will provide potential directions for novel prevention and treatment strategies.
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Affiliation(s)
- Nael Al Koudsi
- Department of Pharmacology, Centre for Addiction and Mental Health, University of Toronto, Canada
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