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Veerappa A, Pendyala G, Guda C. A systems omics-based approach to decode substance use disorders and neuroadaptations. Neurosci Biobehav Rev 2021; 130:61-80. [PMID: 34411560 PMCID: PMC8511293 DOI: 10.1016/j.neubiorev.2021.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 07/23/2021] [Accepted: 08/14/2021] [Indexed: 11/15/2022]
Abstract
Substance use disorders (SUDs) are a group of neuropsychiatric conditions manifesting due to excessive dependence on potential drugs of abuse such as psychostimulants, opioids including prescription opioids, alcohol, inhalants, etc. Experimental studies have generated enormous data in the area of SUDs, but outcomes from such data have remained largely fragmented. In this review, we attempt to coalesce these data points providing an important first step towards our understanding of the etiology of SUDs. We propose and describe a 'core addictome' pathway that behaves central to all SUDs. Besides, we also have made some notable observations paving way for several hypotheses; MECP2 behaves as a master switch during substance use; five distinct gene clusters were identified based on respective substance addiction; a central cluster of genes serves as a hub of the addiction pathway connecting all other substance addiction clusters. In addition to describing these findings, we have emphasized the importance of some candidate genes that are of substantial interest for further investigation and serve as high-value targets for translational efforts.
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Affiliation(s)
- Avinash Veerappa
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Gurudutt Pendyala
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Child Health Research Institute, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - Chittibabu Guda
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, USA; Center for Biomedical Informatics Research and Innovation, University of Nebraska Medical Center, Omaha, NE, 68198, USA.
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Genome-wide linkage scan of antisocial behavior, depression, and impulsive substance use in the UCSF family alcoholism study. Psychiatr Genet 2013; 22:235-44. [PMID: 22517380 DOI: 10.1097/ypg.0b013e328353fb77] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Epidemiological and clinical studies suggest that the rates of antisocial behavior, depression, and impulsive substance use are increased among individuals diagnosed with alcohol dependence relative to those who are not. Thus, the present study conducted genome-wide linkage scans of antisocial behavior, depression, and impulsive substance use in the University of California at San Francisco Family Alcoholism Study. METHODS Antisocial behavior, depressive symptoms, and impulsive substance use were assessed using three scales from the Minnesota Multiphasic Personality Inventory - 2nd ed.: the Antisocial Practices content scale, the Depression content scale, and the revised MacAndrew Alcoholism scale. Linkage analyses were carried out using a variance components approach. RESULTS Suggestive evidence of linkage to three genomic regions independent of alcohol and cannabis dependence diagnostic status was observed: the Antisocial Practices content scale showed evidence of linkage to chromosome 13 at 11 cM, the MacAndrew Alcoholism scale showed evidence of linkage to chromosome 15 at 47 cM, and all three scales showed evidence of linkage to chromosome 17 at 57-58 cM. CONCLUSION Each of these regions has shown previous evidence of linkage and association to substance dependence as well as other psychiatric disorders such as mood and anxiety disorders, attention-deficit hyperactivity disorder, and schizophrenia, thus suggesting potentially broad relations between these regions and psychopathology.
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Han S, Gelernter J, Luo X, Yang BZ. Meta-analysis of 15 genome-wide linkage scans of smoking behavior. Biol Psychiatry 2010; 67:12-9. [PMID: 19819424 PMCID: PMC2975396 DOI: 10.1016/j.biopsych.2009.08.028] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Revised: 08/22/2009] [Accepted: 08/25/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND A genetic contribution to smoking behavior is well-established. To identify loci that increase the risk for smoking behavior, many genome-wide linkage scans have been performed with various smoking behavior assessments. Numerous putative susceptibility loci have been identified, but only a few of these were replicated in independent studies. METHODS We used genome search meta-analysis (GSMA) to identify risk loci by pooling all available independent genome scan results on smoking behavior. Additionally, to minimize locus heterogeneity, subgroup analyses of the smoking behavior assessed by the Fagerstrom Test for Nicotine Dependence (FTND) and maximum number of cigarettes smoked in a 24-hour period (MaxCigs24) were carried out. Samples of European ancestry were also analyzed separately. RESULTS A total number of 15 genome scan results were available for analysis, including 3404 families with 10,253 subjects. Overall, the primary GSMA across all smoking behavior identified a genome-wide suggestive linkage in chromosome 17q24.3-q25.3 (p(SR) = .001). A secondary analysis of FTND in European-ancestry samples (625 families with 1878 subjects) detected a genome-wide suggestive linkage in 5q33.1-5q35.2 (p(SR) = .0076). Subgroup analysis of MaxCigs24 (966 families with 3273 subjects) identified a genome-wide significant linkage in 20q13.12-q13.32 (p(SR) = .00041, p(OR) = .048), where a strongly supported nicotine dependence candidate gene, CHRNA4, is located. CONCLUSIONS The regions identified in the current study deserve close attention and will be helpful for candidate gene identification or target re-sequencing studies in the future.
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Affiliation(s)
- Shizhong Han
- Department of Psychiatry, Division of Human Genetics, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Joel Gelernter
- Department of Psychiatry, Division of Human Genetics, Yale University School of Medicine, New Haven, CT 06511, USA,Department of Genetics, Yale University School of Medicine, New Haven, CT 06511, USA,Department of Neurobiology, Yale University School of Medicine, New Haven, CT 06511, USA,VA CT Healthcare Center 116A2; 950 Campbell Avenue; West Haven, CT 06516
| | - Xingguang Luo
- Department of Psychiatry, Division of Human Genetics, Yale University School of Medicine, New Haven, CT 06511, USA,VA CT Healthcare Center 116A2; 950 Campbell Avenue; West Haven, CT 06516
| | - Bao-Zhu Yang
- Department of Psychiatry, Division of Human Genetics, Yale University School of Medicine, New Haven, CT 06511, USA,VA CT Healthcare Center 116A2; 950 Campbell Avenue; West Haven, CT 06516,Corresponding Author: Bao-Zhu Yang, PhD; Yale University School of Medicine, Department of Psychiatry, Division of Human Genetics in Psychiatry; VA CT 116A2; 950 Campbell Avenue; West Haven, CT 06516; telephone: 203-932-5711 ext 3590; fax, 203-937-4741;
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Pergadia ML, Agrawal A, Loukola A, Montgomery GW, Broms U, Saccone SF, Wang JC, Todorov AA, Heikkilä K, Statham DJ, Henders AK, Campbell MJ, Rice JP, Todd RD, Heath AC, Goate AM, Peltonen L, Kaprio J, Martin NG, Madden PAF. Genetic linkage findings for DSM-IV nicotine withdrawal in two populations. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:950-9. [PMID: 19180564 PMCID: PMC2995916 DOI: 10.1002/ajmg.b.30924] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Nicotine withdrawal (NW) is both an important contributor to difficulty quitting cigarettes and because of mood-related withdrawal symptoms a problem of particular relevance to psychiatry. Twin-studies suggest that genetic factors influence NW (heritability = 45%). Only one previous linkage study has published findings on NW [Swan et al. (2006); Am J Med Genet Part B 141B:354-360; LOD = 2.7; Chr. 6 at 159 cM]. As part of an international consortium, genome-wide scans (using over 360 autosomal microsatellite markers) and telephone diagnostic interviews were conducted on 289 Australian (AUS) and 161 Finnish (FIN, combined (COMB) N = 450 families) families ascertained from twin registries through index-cases with a lifetime history of cigarette smoking. The statistical approach used an affected-sib-pair design (at least two adult full siblings reported a history of DSM-IV NW) and conducted the linkage analyses using MERLIN. Linkage signals with LOD scores >1.5 were found on two chromosomes: 6 (FIN: LOD = 1.93 at 75 cM) and 11 at two different locations (FIN: LOD = 3.55 at 17 cM, and AUS: LOD = 1.68 with a COMB: LOD = 2.30 at 123 cM). The multipoint LOD score of 3.55 on chromosome 11p15 in FIN met genomewide significance (P = 0.013 with 1,000 simulations). At least four strong candidate genes lie within or near this peak on chromosome 11: DRD4, TPH, TH, and CHRNA10. Other studies have reported that chromosome 11 may harbor genes associated with various aspects of smoking behavior. This study adds to that literature by highlighting evidence for NW.
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Affiliation(s)
- Michele L Pergadia
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
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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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Li MD. Identifying susceptibility loci for nicotine dependence: 2008 update based on recent genome-wide linkage analyses. Hum Genet 2008; 123:119-31. [PMID: 18205015 DOI: 10.1007/s00439-008-0473-0] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Accepted: 01/15/2008] [Indexed: 02/05/2023]
Abstract
Tobacco smoking is a severe health hazard worldwide, as nearly one-third of the global adult population smokes tobacco products. This high prevalence highlights the importance of studying the genetic determinants of nicotine dependence (ND). To identify such genetic factors, more than 20 genome-wide linkage studies have been conducted across different populations using a variety of ND assessment approaches, including smoking quantity (SQ), Heaviness of Smoking Index (HSI), Fagerström Test for Nicotine Dependence (FTND), ever-smoking, habitual smoking, or maximum number of cigarettes smoked in a 24-h period. This review provides a critical update on the progress during the years since our last review, published in 2004, in identifying susceptibility loci for ND. Although a significant number of reported genomic regions did not reach the level of "suggestive" or "significant" linkage and failed to be replicated in other independent studies, thirteen regions, located on chromosomes 3-7, 9-11, 17, 20, and 22, have been found to be suggestive or significant in at least two independent samples. Among them, the regions on chromosomes 9 (91.9-136.5 cM), 10, 11, and 17 have received the strongest support. A summary of eight regions that have been nominated for "significant" linkage to ND is provided.
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Affiliation(s)
- Ming D Li
- Department of Psychiatry and Neurobehavioral Sciences, Section of Neurobiology, University of Virginia, 1670 Discovery Drive, Suite 110, Charlottesville, VA 22911, USA.
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Liu Y, Li GP, Rickords LF, White KL, Sessions BR, Aston KI, Bunch TD. Effect of nicotine on in vitro maturation of bovine oocytes. Anim Reprod Sci 2008; 103:13-24. [PMID: 17178443 DOI: 10.1016/j.anireprosci.2006.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2006] [Accepted: 11/22/2006] [Indexed: 11/30/2022]
Abstract
The putative effect of nicotine on maturation and the chromosomal complement of bovine oocytes were investigated in the present study. Cumulus-enclosed oocytes were incubated in maturation medium with 0, 0.5, 1.0, 2.5, 5.0, and 10.0 mmol concentrations of nicotine. The results indicated that: (1) nicotine affected cumulus cell expansion in a dose-dependent manner and the perivitelline space failed to form when concentrations were equal to or greater than 5.0 mmol; (2) oocytes treated with 0.5 and 1.0 mmol nicotine concentrations resulted in maturation rates (83.3% and 85.9%, respectively) which was similar to the control (86.2%), whereas treatment with 2.5 and 5.0 mmol concentrations significantly decreased maturation rates to 70.2% and 26.7%, respectively; (3) nicotine at or over 2.5 mmol caused extremely irregular meiotic spindles and interrupted microfilament organization; (4) chromosomal analyses of oocytes with PB1 showed that oocytes derived from 0.5 and 1.0 mmol nicotine groups had haploid complements similar to the control (87-90%), but when the concentrations were increased to 2.5 and 5.0 mmol the haploid state was significantly reduced to around 70%; (5) oocytes at GVBD (germinal vesicle breakdown) and metaphase I stages were less affected by nicotine at 5.0 and 10.0 mmol concentrations than GV-stage oocytes; (6) maturation rates of the short-term nicotine-treated oocytes could be improved when subsequently incubated in normal maturation medium. Prolonged culture of nicotine-pretreated oocytes resulted in self-activation and some oocytes formed 1 or 2 pronuclei. In conclusion, nicotine affects bovine oocyte cumulus cell expansion, maturation rate, and chromosomal complement in a dose-dependent and an oocyte-stage-dependent manner.
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Affiliation(s)
- Ying Liu
- Department of Animal, Dairy and Veterinary Sciences, and Center for Integrated Biosystems, Utah State University, Logan, UT 84321, United States
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Huang W, Ma JZ, Payne TJ, Beuten J, Dupont RT, Li MD. Significant association of DRD1 with nicotine dependence. Hum Genet 2007; 123:133-40. [PMID: 18092181 DOI: 10.1007/s00439-007-0453-9] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 12/11/2007] [Indexed: 10/22/2022]
Abstract
Epidemiologic studies have strongly implicated genetics in smoking behavior. Genes in the dopaminergic system, which mediates the reinforcing and dependence-producing properties of nicotine, are plausible candidates for roles in nicotine dependence (ND). In this study, we examined five single-nucleotide polymorphisms (SNPs) within or near the dopamine D(1) receptor gene (DRD1) for their association with ND, which was assessed by smoking quantity (SQ), the Heaviness of Smoking Index (HSI), and the Fagerström Test for ND (FTND). The samples were obtained from 2,037 participants representing 200 European American (EA) and 402 African American (AA) families. Although we found significant associations of SNPs rs265973, rs686, and rs4532 in the AA sample; of rs4532 in the EA sample; and of rs265975, rs686, and rs4532 in the pooled sample with various ND measures, only the association of rs686 in the AA sample and of rs686 and rs4532 in the pooled sample remained significant after correction for multiple testing. Haplotype-based association analysis revealed that haplotype C-T-A, formed by rs265973, rs265975, and rs686, was significantly associated with all three ND measures in both the AA and the pooled sample. Another haplotype, T-A-T, formed by rs265975, rs686, and rs4532, showed a significant association with FTND in the pooled sample. Furthermore, in a luciferase reporter assay, rs686, located in the 3' untranslated region, caused differential luciferase activities, indicating that rs686 is a functional polymorphism affecting expression of DRD1.
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Affiliation(s)
- Weihua Huang
- Department of Psychiatry and Neurobehavioral Sciences, Section of Neurobiology, University of Virginia, 1670 Discovery Drive, Suite 125, Charlottesville, VA 22911, USA
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9
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Liu Y, Li GP, White KL, Rickords LF, Sessions BR, Aston KI, Bunch TD. Nicotine alters bovine oocyte meiosis and affects subsequent embryonic development. Mol Reprod Dev 2007; 74:1473-82. [PMID: 17440977 DOI: 10.1002/mrd.20717] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The effects of nicotine on nuclear maturation and meiotic spindle dynamics of bovine oocytes and subsequent embryonic development were investigated. Maturation rates (85%-94%) derived from nicotine treatments at 0.01 to 1.0 mM were similar to the control (86%), but significantly decreased at 2.0 to 6.0 mM. Haploid complements of metaphase II oocytes in 0.01 to 1.0 mM nicotine (approximately 90%) were similar to the control, while lower (ranged from 63% to 76%, P < 0.05 or P < 0.01) haploid oocytes were observed in the 2.0 to 6.0 mM nicotine groups. The majority of the PB1-free oocytes derived from 3.0 to 6.0 mM nicotine treatments were diploidy (2n = 60). Spindle microtubules changed from characteristically being asymmetrical in the controls to being equally distributed into two separate chromosome groups in the nicotine treatments. Nicotine disorganized the microfilament organization and inhibited the movement of anaphase or telophase chromosomes to the cortical area. The inhibited two chromosome groups became two spindles that either moved close in proximity or merged entirely together resulting in diploidy within the affected oocyte. Nicotine treatment significantly reduced the rate of cleavage and blastocyst development after parthenogenetic activation. Diploidy and cell number were drastically reduced in the resultant blastocysts. In conclusion, nicotine can alter the normal process of bovine oocyte meiosis and affects subsequent embryonic development.
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Affiliation(s)
- Ying Liu
- Department of Animal, Dairy and Veterinary Sciences, and Center for Integrated Biosystems, Utah State University, Logan, Utah 84322-4815, USA
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Lessov-Schlaggar CN, Pergadia ML, Khroyan TV, Swan GE. Genetics of nicotine dependence and pharmacotherapy. Biochem Pharmacol 2007; 75:178-95. [PMID: 17888884 PMCID: PMC2238639 DOI: 10.1016/j.bcp.2007.08.018] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 08/13/2007] [Accepted: 08/15/2007] [Indexed: 12/22/2022]
Abstract
Nicotine dependence is substantially heritable. Several regions across the genome have been implicated in containing genes that confer liability to nicotine dependence and variation in individual genes has been associated with nicotine dependence. Smoking cessation measures are also heritable, and measured genetic variation is associated with nicotine dependence treatment efficacy. Despite significant strides in the understanding of the relative contribution of genetic and environmental factors to nicotine dependence and treatment, emergent challenges necessitate interdisciplinary coordinated effort for effective problem solving. These challenges include refinement of the nicotine dependence phenotype, better understanding of the dynamic interplay between genes and environment in nicotine dependence etiology, application and development of molecular and statistical methodology that can adequately address vast amounts of data, and continuous translational cross-talk.
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Uhl GR, Drgon T, Johnson C, Fatusin OO, Liu QR, Contoreggi C, Li CY, Buck K, Crabbe J. "Higher order" addiction molecular genetics: convergent data from genome-wide association in humans and mice. Biochem Pharmacol 2007; 75:98-111. [PMID: 17764662 PMCID: PMC3282179 DOI: 10.1016/j.bcp.2007.06.042] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 06/26/2007] [Accepted: 06/28/2007] [Indexed: 02/05/2023]
Abstract
Family, adoption and twin data each support substantial heritability for addictions. Most of this heritable influence is not substance-specific. The overlapping genetic vulnerability for developing dependence on a variety of addictive substances suggests large roles for "higher order" pharamacogenomics in addiction molecular genetics. We and others have now completed genome-wide association (GWA) studies of DNAs from individuals with dependence on a variety of addictive substances versus appropriate controls. Recently reported replicated GWA observations identify a number of genes based on comparisons between controls and European-American and African-American polysubstance abusers. Here we review the convergence between these results and data that compares control samples and (a) alcohol-dependent European-Americans, (b) methamphetamine-dependent Asians and (c) nicotine dependent samples from European backgrounds. We also compare these human data to quantitative trait locus (QTL) results from studies of addiction-related phenotypes in mice that focus on alcohol, methamphetamine and barbiturates. These comparisons support a genetic architecture built from largely polygenic contributions of common allelic variants to dependence on a variety of legal and illegal substances. Many of the gene variants identified in this way are likely to alter specification and maintenance of neuronal connections.
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Affiliation(s)
- George R Uhl
- Molecular Neurobiology Branch, NIH-IRP (NIDA), Suite 3510, 333 Cassell Drive Baltimore, MD 21224, USA.
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12
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Saccone SF, Pergadia ML, Loukola A, Broms U, Montgomery GW, Wang JC, Agrawal A, Dick DM, Heath AC, Todorov AA, Maunu H, Heikkila K, Morley KI, Rice JP, Todd RD, Kaprio J, Peltonen L, Martin NG, Goate AM, Madden PAF. Genetic linkage to chromosome 22q12 for a heavy-smoking quantitative trait in two independent samples. Am J Hum Genet 2007; 80:856-66. [PMID: 17436240 PMCID: PMC1852734 DOI: 10.1086/513703] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Accepted: 02/07/2007] [Indexed: 11/03/2022] Open
Abstract
We conducted a genomewide linkage screen of a simple heavy-smoking quantitative trait, the maximum number of cigarettes smoked in a 24-h period, using two independent samples: 289 Australian and 155 Finnish nuclear multiplex families, all of which were of European ancestry and were targeted for DNA analysis by use of probands with a heavy-smoking phenotype. We analyzed the trait, using a regression of identity-by-descent allele sharing on the sum and difference of the trait values for relative pairs. Suggestive linkage was detected on chromosome 22 at 27-29 cM in each sample, with a LOD score of 5.98 at 26.96 cM in the combined sample. After additional markers were used to localize the signal, the LOD score was 5.21 at 25.46 cM. To assess the statistical significance of the LOD score in the combined sample, 1,000 simulated genomewide screens were conducted, resulting in an empirical P value of .006 for the LOD score of 5.21. This linkage signal is driven mainly by the microsatellite marker D22S315 (22.59 cM), which had a single-point LOD score of 5.41 in the combined sample and an empirical P value <.001 from 1,000 simulated genomewide screens. This marker is located within an intron of the gene ADRBK2, encoding the beta-adrenergic receptor kinase 2. Fine mapping of this linkage region may reveal variants contributing to heaviness of smoking, which will lead to a better understanding of the genetic mechanisms underlying nicotine dependence.
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Affiliation(s)
- Scott F Saccone
- Department of Psychiatry, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Uhl GR, Liu QR, Drgon T, Johnson C, Walther D, Rose JE. Molecular genetics of nicotine dependence and abstinence: whole genome association using 520,000 SNPs. BMC Genet 2007; 8:10. [PMID: 17407593 PMCID: PMC1853105 DOI: 10.1186/1471-2156-8-10] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Accepted: 04/03/2007] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Classical genetic studies indicate that nicotine dependence is a substantially heritable complex disorder. Genetic vulnerabilities to nicotine dependence largely overlap with genetic vulnerabilities to dependence on other addictive substances. Successful abstinence from nicotine displays substantial heritable components as well. Some of the heritability for the ability to quit smoking appears to overlap with the genetics of nicotine dependence and some does not. We now report genome wide association studies of nicotine dependent individuals who were successful in abstaining from cigarette smoking, nicotine dependent individuals who were not successful in abstaining and ethnically-matched control subjects free from substantial lifetime use of any addictive substance. RESULTS These data, and their comparison with data that we have previously obtained from comparisons of four other substance dependent vs control samples support two main ideas: 1) Single nucleotide polymorphisms (SNPs) whose allele frequencies distinguish nicotine-dependent from control individuals identify a set of genes that overlaps significantly with the set of genes that contain markers whose allelic frequencies distinguish the four other substance dependent vs control groups (p < 0.018). 2) SNPs whose allelic frequencies distinguish successful vs unsuccessful abstainers cluster in small genomic regions in ways that are highly unlikely to be due to chance (Monte Carlo p < 0.00001). CONCLUSION These clustered SNPs nominate candidate genes for successful abstinence from smoking that are implicated in interesting functions: cell adhesion, enzymes, transcriptional regulators, neurotransmitters and receptors and regulation of DNA, RNA and proteins. As these observations are replicated, they will provide an increasingly-strong basis for understanding mechanisms of successful abstinence, for identifying individuals more or less likely to succeed in smoking cessation efforts and for tailoring therapies so that genotypes can help match smokers with the treatments that are most likely to benefit them.
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Affiliation(s)
- George R Uhl
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
| | - Qing-Rong Liu
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
| | - Tomas Drgon
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
| | - Catherine Johnson
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
| | - Donna Walther
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
| | - Jed E Rose
- Molecular Neurobiology Branch, NIH-IRP, NIDA, Suite 3510, 333 Cassell Drive Baltimore, Maryland 21224, USA
- Dept of Psychiatry and Center for Nicotine and Smoking Cessation Research, Duke University, Durham NC 27708, USA
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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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Li MD, Payne TJ, Ma JZ, Lou XY, Zhang D, Dupont RT, Crews KM, Somes G, Williams NJ, Elston RC. A genomewide search finds major susceptibility loci for nicotine dependence on chromosome 10 in African Americans. Am J Hum Genet 2006; 79:745-51. [PMID: 16960812 PMCID: PMC1592559 DOI: 10.1086/508208] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Accepted: 07/28/2006] [Indexed: 12/11/2022] Open
Abstract
Epidemiological studies have demonstrated that genetic factors account for at least 50% of the liability for nicotine dependence (ND). Although several linkage studies have been conducted, all samples to date were primarily of European origin. In this study, we conducted a genomewide scan of 1,261 individuals, representing 402 nuclear families, of African American (AA) origin. We examined 385 autosomal microsatellite markers for ND, which was assessed by smoking quantity (SQ), the Heaviness of Smoking Index (HSI), and the Fagerstrom Test for ND (FTND). After performing linkage analyses using various methods implemented in the GENEHUNTER and S.A.G.E. programs, we found a region near marker D10S1432 on chromosome 10q22 that showed a significant linkage to indexed SQ, with a maximum LOD score of 4.17 at 92 cM and suggestive linkage to HSI, SQ, and log-transformed SQ. Additionally, we identified three regions that met the criteria for suggestive linkage to at least one ND measure: on chromosomes 9q31 at marker D9S1825, 11p11 between markers D11S1993 and D11S1344, and 13q13 between markers D13S325 and D13S788. Other locations on chromosomes 15p11, 17q25, and 18q12 exhibited some evidence of linkage for ND (LOD >1.44). The four regions with significant or suggestive linkage were positive for multiple ND measures by multiple statistical methods. Some of these regions have been linked to smoking behavior at nominally significant levels in other studies, which provides independent replication of the regions for ND in different cohorts. In summary, we found significant linkage on chromosome 10q22 and suggestive linkage on chromosomes 9, 11, and 13 for major genetic determinants of ND in an AA sample. Further analysis of these positive regions by fine mapping and/or association analysis is thus warranted. To our knowledge, this study represents the first genomewide linkage scan of ND in an AA sample.
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Affiliation(s)
- Ming D Li
- Department of Psychiatric Medicine, University of Virginia, Charlottesville, VA 22911, USA.
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16
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Swan GE, Hops H, Wilhelmsen KC, Lessov-Schlaggar CN, Cheng LSC, Hudmon KS, Amos C, Feiler HS, Ring HZ, Andrews JA, Tildesley E, Benowitz N. A genome-wide screen for nicotine dependence susceptibility loci. Am J Med Genet B Neuropsychiatr Genet 2006; 141B:354-60. [PMID: 16671072 PMCID: PMC2563426 DOI: 10.1002/ajmg.b.30315] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genome-wide model free linkage analysis was conducted for nicotine dependence and tobacco use phenotypes in 607 members of 158 nuclear families consisting of at least two ever smokers (100 or more cigarettes smoked in lifetime). DNA from whole blood was genotyped for 739 autosomal microsatellite polymorphisms with an average inter-marker distance of 4.6 cM. A peak LOD score of 2.7 was observed on chromosome 6 for scores for the Fagerström Test for Nicotine Dependence. Exploratory analyses were conducted to determine whether sequence variation at other loci affected other measures of dependence or tobacco use. Four additional loci with LOD scores of 2.7 or more were associated with alternative measures of nicotine dependence, one with current frequency of use, and one with smoking cessation. Several of the corresponding support intervals were near putative loci reported previously (on chromosomes 6, 7, and 8) while others appear to be novel (on chromosomes 5, 16, and 19).
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Affiliation(s)
- Gary E. Swan
- Center for Health Sciences, SRI International, Menlo Park, California
| | - Hyman Hops
- Oregon Research Institute, Eugene, Oregon
| | - Kirk C. Wilhelmsen
- Departments of Neurology and Pharmacology, University of California, San Francisco
- Ernest Gallo Clinic and Research Center
| | | | | | - Karen S. Hudmon
- Center for Health Sciences, SRI International, Menlo Park, California
| | | | | | - Huijun Z. Ring
- Center for Health Sciences, SRI International, Menlo Park, California
| | | | | | - Neal Benowitz
- Division of Pharmacology University of California, San Francisco, San Francisco, California
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17
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Ehlers CL, Wilhelmsen KC. Genomic screen for loci associated with tobacco usage in Mission Indians. BMC MEDICAL GENETICS 2006; 7:9. [PMID: 16472381 PMCID: PMC1386651 DOI: 10.1186/1471-2350-7-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2005] [Accepted: 02/10/2006] [Indexed: 11/10/2022]
Abstract
Background The prevalence of tobacco usage in Native American adults and adolescents is higher than any other racial or ethnic group, yet biological risk and protective factors underlying tobacco use in this ethnic group remain unknown. A genome scan for loci associated with tobacco use phenotypes was performed with data collected from a community sample of Mission Indians residing in Southwest California. Methods A structured diagnostic interview was used to define two tobacco use phenotypes: 1) any regular tobacco usage (smoked daily for one month or more) and 2) persistent tobacco usage (smoked at least 10 cigarettes a day for more than one year). Heritability was determined and a linkage analysis was performed, using genotypes for a panel 791 microsatellite polymorphisms, for the two phenotypes using variance component methods implemented in SOLAR. Results Analyses of multipoint variance component LOD scores for the two tobacco use phenotypes revealed two scores that exceeded 2.0 for the regular use phenotype: one on chromosomes 6 and one on 8. Four other loci on chromosomes 1,7,13, and 22 were found with LOD scores between 1.0 and 1.5. Two loci of interest were found on chromosomes 1 and 4 for the persistent use phenotype with LOD scores between 1.3–1.5. Bivariate linkage analysis was conducted at the site on chromosome 4 for persistent tobacco use and an alcohol drinking severity phenotype previously identified at this site. The maximum LOD score for the bivariate analysis for the region was 3.4, however, there was insufficient power to exclude coincident linkage. Conclusion While not providing evidence for linkage to specific chromosomal regions these results identify regions of interest in the genome in this Mission Indian population, for tobacco usage, some of which were identified in previous genome scans of non-native populations. Additionally, these data lend support for the hypothesis that cigarette smoking, alcohol dependence and other consumptive behaviors may share some common risk and/or protective factors in this Mission Indian population.
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Affiliation(s)
- Cindy L Ehlers
- Departments of Molecular and Experimental Medicine, and Neuropharmacology, The Scripps Research Institute, La Jolla California, USA
| | - Kirk C Wilhelmsen
- Departments of Genetics and Neurology, The Carolina Center for Genome Sciences and the Bowles Center for Alcohol Studies, University of North Carolina, North Carolina, USA
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18
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Vink JM, Posthuma D, Neale MC, Eline Slagboom P, Boomsma DI. Genome-wide Linkage Scan to Identify Loci for Age at First Cigarette in Dutch Sibling Pairs. Behav Genet 2005; 36:100-11. [PMID: 16374522 DOI: 10.1007/s10519-005-9012-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Accepted: 07/25/2005] [Indexed: 01/24/2023]
Abstract
The heritability of age at first cigarette was estimated in 5883 Dutch twins and siblings registered with the Netherlands Twin Register. Heritability was 60% for males and 39% for females. Shared environmental influences were found in females only (30%). Linkage analyses were performed on data of 422 DZ twins and siblings from 175 families, forming 368 sibling pairs. Genomic regions that may harbor susceptibility loci for age at first cigarette with LOD score greater than 2 were detected on chromosomes 5, 14 and 22. A simultaneous analysis of these three genomic regions showed that most of the variance was explained by the linkage effect on chromosome 5 (205 cM). This peak encloses the D1A dopamine receptor gene which is a functional candidate gene for smoking behavior.
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Affiliation(s)
- Jacqueline M Vink
- Department of Biological Psychology, Vrije Universiteit, BT Amsterdam, The Netherlands.
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19
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Morley KI, Medland SE, Ferreira MA, Lynskey MT, Montgomery GW, Heath AC, Madden PA, Martin NG. A Possible Smoking Susceptibility Locus on Chromosome 11p12: Evidence from Sex-limitation Linkage Analyses in a Sample of Australian Twin Families. Behav Genet 2005; 36:87-99. [PMID: 16365831 DOI: 10.1007/s10519-005-9004-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2005] [Accepted: 08/04/2005] [Indexed: 12/23/2022]
Abstract
Many twin studies have identified sex differences in the influence of genetic and environmental factors on smoking behaviors. We explore the evidence for sex differences for smoking initiation and cigarette consumption in a sample of Australian twin families, and extend these models to incorporate sex differences in linkage analyses for these traits. We further examine the impact of including or excluding non-smokers in genetic analyses of tobacco consumption. Accounting for sex differences improved linkage results in some instances. We identified one region suggestive of linkage on chromosome 11p12. This locus, as well as another region identified on chromosome 6p12, replicates regions identified in previous studies.
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Affiliation(s)
- Katherine I Morley
- Genetic Epidemiology, Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland, Australia.
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20
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Vink JM, Willemsen G, Boomsma DI. Heritability of smoking initiation and nicotine dependence. Behav Genet 2005; 35:397-406. [PMID: 15971021 DOI: 10.1007/s10519-004-1327-8] [Citation(s) in RCA: 216] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2004] [Accepted: 11/10/2004] [Indexed: 10/25/2022]
Abstract
In contrast to other aspects of smoking behavior, little attention has been paid to the genetics of nicotine dependence. In this paper, three models (single liability dimension, independent liability dimension and combined model) have been applied to data on smoking initiation and nicotine dependence (n = 1572 Dutch twin pairs, mean age 30.5). A combined model best described the data. This model postulates a smoking initiation dimension and a nicotine dependence dimension, which are not independent. For both males and females, individual differences in smoking initiation were explained by genetic (44%), shared environmental (51%) and unique environmental (5%) influences. The nicotine dependence dimension was influenced only by genetic (75%) and unique environmental (25%) factors. The substantial impact of genetic factors on nicotine dependence emphasizes the need for further research to localize and identify specific genes and pathways involved in nicotine dependence.
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Affiliation(s)
- Jacqueline M Vink
- Department of Biological Psychology, Vrije Universiteit, Amsterdam, The Netherlands.
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21
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Wang D, Ma JZ, Li MD. Mapping and verification of susceptibility loci for smoking quantity using permutation linkage analysis. THE PHARMACOGENOMICS JOURNAL 2005; 5:166-72. [PMID: 15724146 DOI: 10.1038/sj.tpj.6500304] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Nicotine dependence is the most prevalent form of drug addiction in the US and throughout the world. Epidemiological studies demonstrate that genetics accounts for at least 50% of the liability to nicotine dependence. However, there have been very limited linkage studies providing convincing evidence of susceptibility genomic loci for this disorder. In this study, we conducted genome-wide permutation linkage analyses on the smoking data collected between 1970 and 1972 of the Framingham Heart Study (FHS) to account for the abnormality associated with the smoking quantity (defined as the number of cigarettes smoked per day). We used empirical thresholds obtained from permutation tests to determine the significance of each genomic region. The variance component method implemented in SOLAR was used for the analysis. Under the empirical genome-wide thresholds determined specifically for the FHS smoking data, we found two highly or near-highly significant linkages of nicotine dependence on chromosomes 1 and 4 (P=0.001) and eight significant linkages on chromosomes 3, 7, 8, 9, 11, 16, 17, and 20 (P<0.05). These findings strongly indicate that some of these regions may harbor susceptibility loci for nicotine dependence. Further analysis of these positive regions by fine mapping and/or association analysis is warranted. To our knowledge, this study presents the most convincing linkage evidence for nicotine dependence in the field.
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Affiliation(s)
- D Wang
- Program in Genomics and Bioinformatics on Drug Addiction, Department of Psychiatry, The University of Texas Health Science Center, San Antonio, TX 78229, USA
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Abstract
Smoking behaviour is influenced by both genetic and environmental factors. Many years of twin and adoption studies have demonstrated that heritability is at least 50% responsible for both smoking initiation and smoking persistence. Furthermore, the extent, to which genetic and environmental factors contribute to smoking behaviour, is significantly different in men and women. Linkage analyses from several independent studies provide evidences for suggested linkage of smoking behaviour to chromosomes 1, 2, 4, 5, 6, 9, 10, 11, 14, 17, 18 and 21. However, almost none of these loci have been replicated yet. Furthermore, numerous population-based association studies have been performed to examine the effects of a number of candidate genes, such as cytochrome P450, dopamine receptor (DR) and transporter, serotonin transporter and nicotinic acetylcholine receptor, on smoking behaviour. However, many of these reports have not yet received independent confirmation. Of these candidate genes, the D2 dopamine receptor (DRD2) gene has been extensively studied. Meta-analysis of 12 reported studies showed a significantly higher prevalence of the DRD2 TaqI A1 allele in smokers than that in non-smokers (p < 0.0001; pooled OR = 1.50; 95% CI = 1.33-1.70). For other candidate genes, insufficient published studies are available to allow a meta-analysis to be performed, or meta-analysis showed no significant difference between smokers and non-smokers. More studies are necessary to determine whether these genes play a significant role in smoking behaviour.
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Affiliation(s)
- M D Li
- Program in Genomics and Bioinformatics on Drug Addiction, Department of Psychiatry, The University of Texas Health Science Center, Floyd Curl Drive, San Antonio 78229, USA.
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Abstract
Drug use is a complex behavior influenced by multiple biological, family, and sociocultural factors. The concurrent use/misuse of multiple drugs is often seen and drug use also co-occurs with other psychiatric conditions. Behavior and molecular genetic studies support an important posited role of genes in drug use. This posited genetic risk does not appear to be conferred by one or two major genes manifesting large effects, but rather by a number of genes manifesting smaller effects. Genetic factors explain, on average, only about half of the total variability in drug use, with the remaining variability influenced by environmental factors. Also, genetic risk may be differentially expressed in the presence vs. absence of particular environmental conditions. Thus, investigation of environmental factors and their interaction with genetic risk is a necessary component of genetic research. While the full potential of genetic investigations for the prevention of drug misuse has yet to be realized, an example of the impact of risk factor modification under various conditions of gene-environment interaction is provided, and the implications for use of genetic information in drug-misuse prevention are discussed. The multifactorial nature of drug use necessitates coordinated investigation from multiple disciplines and timely dissemination of scientific findings. In addition, this work demands adherence to the highest standards of confidentiality and ethical use of genetic information to best inform future prevention efforts.
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Affiliation(s)
- Christina N Lessov
- Center for Health Sciences, SRI International, Menlo Park, California 94025, USA.
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Saccone NL, Goode EL, Bergen AW. Genetic analysis workshop 13: Summary of analyses of alcohol and cigarette use phenotypes in the Framingham Heart Study. Genet Epidemiol 2003; 25 Suppl 1:S90-7. [PMID: 14635174 DOI: 10.1002/gepi.10289] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Data from the Framingham Heart Study were provided for Genetic Analysis Workshop 13. This paper summarizes six contributed papers that focused on the analysis of the longitudinal alcohol and/or cigarette use phenotypes available in these data, with the goal of detecting genes influencing these traits. For several of these contributions, the primary phenotype was maximum daily substance use reported over the longitudinal data. Others focused on a cross section by taking the daily use reported at a fixed time interval for all individuals, and others considered dichotomous phenotypes defined by thresholds of use. A variety of covariates were considered, including age (or year of birth) and sex. Most studies included unexposed individuals (those reporting no alcohol/cigarette use at all available assessments) in the linkage analyses, though one study compared results when defining the phenotype for unexposed individuals to be zero vs. defining the phenotype for unexposed individuals to be unknown. Linkage findings varied across studies. However, there was some concordance of evidence on chromosome 9 for alcohol traits, and of weaker evidence on chromosome 20 for cigarette traits. Analytical issues arose which may be crucial for genetic studies of substance use and dependence, including the choice of how to handle unexposed or substance-naive individuals, use of dichotomous vs. quantitative traits, and consideration of transformations and covariates.
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Affiliation(s)
- Nancy L Saccone
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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