1
|
Ehlers CL, Gizer IR, Bizon C, Slutske W, Peng Q, Schork NJ, Wilhelmsen KC. Single nucleotide polymorphisms in the REG-CTNNA2 region of chromosome 2 and NEIL3 associated with impulsivity in a Native American sample. GENES BRAIN AND BEHAVIOR 2016; 15:568-77. [PMID: 27167163 DOI: 10.1111/gbb.12297] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 04/18/2016] [Accepted: 05/09/2016] [Indexed: 12/26/2022]
Abstract
Impulsivity is a multi-faceted construct that, while characterized by a set of correlated dimensions, is centered around a core definition that involves acting suddenly in an unplanned manner without consideration for the consequences of such behavior. Several psychiatric disorders include impulsivity as a criterion, and thus it has been suggested that it may link a number of different behavioral disorders, including substance abuse. Native Americans (NA) experience some of the highest rates of substance abuse of all the US ethnic groups. The described analyses used data from a low-coverage whole genome sequence scan to conduct a genome-wide association study (GWAS) of an impulsivity phenotype in an American Indian community sample (n = 658). Demographic and clinical information were obtained using a semi-structured interview. Impulsivity was assessed using a scale derived from the Maudsley personality inventory that combines both novelty seeking and lack of planning items. The impulsivity score was tested for association with each variant adjusted for demographic variables, and corrected for ancestry and kinship, using emmax. Simulations were conducted to calculate empirical P-values. Genome-wide significant findings were observed for a variant 50-kb upstream from catenin cadherin-associated protein, alpha 2 (CTNNA2), a neuronal-specific catenin, in the REG gene cluster. A meta-analysis of GWAS had previously identified common variants in CTNNA2 as being associated with excitement seeking. A second locus upstream of nei endonuclease VIII-like 3 (NEIL3) on chromosome 4 also achieved genome-wide significance. The association between sequence variants in these regions suggests their potential roles in the genetic regulation of this phenotype in this population.
Collapse
Affiliation(s)
- C L Ehlers
- The Scripps Research Institute, Molecular and Cellular Neuroscience Department, La Jolla, CA
| | - I R Gizer
- Department of Psychological Sciences, University of Missouri, Columbia, MO
| | - C Bizon
- Renaissance Computing Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - W Slutske
- Department of Psychological Sciences, University of Missouri, Columbia, MO
| | - Q Peng
- The Scripps Research Institute, Molecular and Cellular Neuroscience Department, La Jolla, CA.,J Craig Venter Institute, Human Biology, La Jolla, CA
| | - N J Schork
- J Craig Venter Institute, Human Biology, La Jolla, CA
| | - K C Wilhelmsen
- Renaissance Computing Institute, University of North Carolina at Chapel Hill, Chapel Hill, NC.,Department of Genetics and Neurology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| |
Collapse
|
2
|
Gilder DA, Stouffer GM, Lau P, Ehlers CL. Clinical characteristics of alcohol combined with other substance use disorders in an American Indian community sample. Drug Alcohol Depend 2016; 161:222-9. [PMID: 26896167 PMCID: PMC4792738 DOI: 10.1016/j.drugalcdep.2016.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 02/02/2016] [Accepted: 02/03/2016] [Indexed: 10/22/2022]
Abstract
BACKGROUND Alcohol and other substance use disorders (SUD) pose major problems of morbidity and mortality in some American Indian communities, but little is known about the clinical characteristics, risk factors, and consequences of combined alcohol and other substance use disorders (multi-substance use disorder, MSUD) in those communities. METHODS Using the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA), in a community sample of 876 American Indians, the clinical characteristics of lifetime DSM-5 moderate or severe alcohol use disorder alone (AUD alone) (n=146) and MSUD (defined as alcohol and ≥1 other SUD) (n=284) were evaluated and compared to 347 participants with no lifetime SUD (no SUD). RESULTS The majority (57%) of participants with a SUD had multi-substance use disorder and 94% of those were with AUD. Stimulants (cocaine and/or amphetamine) and/or cannabis were the most common other SUDs. Participants with AUD alone were more likely to be male and have an earlier age of first alcohol intoxication than those with no SUD. Those with MSUD were more likely to have dropped out of high school, have antisocial personality disorder (ASPD) or conduct disorder (CD), have earlier ages of first alcohol intoxication and first use of cannabis and stimulants, an earlier age of onset of AUD, and more of several AUD symptoms than those with AUD alone, but the same temporal course and time to remission of AUD. CONCLUSIONS MSUD is prevalent in this sample, is associated with multiple comorbidities and denotes a more severe alcohol syndrome than AUD alone.
Collapse
Affiliation(s)
| | | | | | - Cindy L. Ehlers
- Corresponding author at: The Scripps Research Institute, 10550 North Torrey Pines Road, SP30-1501, La Jolla, CA 92037. Tel.: (858) 784-7058; Fax: (858) 784-7409.,
| |
Collapse
|
3
|
Ehlers CL, Wills DN, Phillips E, Havstad J. Low voltage alpha EEG phenotype is associated with reduced amplitudes of alpha event-related oscillations, increased cortical phase synchrony, and a low level of response to alcohol. Int J Psychophysiol 2015; 98:65-75. [PMID: 26151497 PMCID: PMC4579005 DOI: 10.1016/j.ijpsycho.2015.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 06/11/2015] [Accepted: 07/03/2015] [Indexed: 10/23/2022]
Abstract
Low voltage EEG (LVEEG) is a heritable phenotype that differs depending on ancestral heritage, yet its impact on brain networks and cognition remain relatively unexplored. In this study we assessed energy and task related phase locking of event-related oscillation (EROs), behavioral responses, measures of IQ and personality, and expected responses to alcohol in a large sample of individuals with LVEEG compared to those with higher voltage variants. Participants (n=762) were recruited from a Native American community and completed a diagnostic interview, the Quick Test, the Subjective High Assessment Scale Expectation Version (SHAS-E) and the Maudsley Personality Inventory. Clinical and spectral analyzed EEGs were collected for determination of the presence of a LVEEG variant. EROs were generated using a facial expression recognition task. Participants with LVEEG (n=451) were significantly more likely to be older, married and have higher degrees of Native American heritage but did not differ in gender, income or education. Individuals with LVEEG were also found to have decreased energy in their alpha EROs, increased phase locking between stimulus trials, and increased phase-locking between cortical brain areas. No significant differences in the cognitive tests, personality variables or alcohol dependence or anxiety diagnoses were found, however, individuals with LVEEG did report a larger number of drinks ever consumed in a 24-h period and a less intense expected response to alcohol. These data suggest that alpha power in the resting EEG is highly associated with energy and cortical connectivity measures generated by event-related stimuli, as well as potentially increased risk for alcohol use.
Collapse
Affiliation(s)
- Cindy L Ehlers
- The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA, United States.
| | - Derek N Wills
- The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA, United States
| | - Evelyn Phillips
- The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA, United States
| | - James Havstad
- The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA, United States
| |
Collapse
|
4
|
Ehlers CL, Gizer IR, Gilder DA, Ellingson JM, Yehuda R. Measuring historical trauma in an American Indian community sample: contributions of substance dependence, affective disorder, conduct disorder and PTSD. Drug Alcohol Depend 2013; 133:180-7. [PMID: 23791028 PMCID: PMC3810370 DOI: 10.1016/j.drugalcdep.2013.05.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Revised: 05/08/2013] [Accepted: 05/08/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND The American Indian experience of historical trauma is thought of as both a source of intergenerational trauma responses as well as a potential causative factor for long-term distress and substance abuse among communities. The aims of the present study were to evaluate the extent to which the frequency of thoughts of historical loss and associated symptoms are influenced by: current traumatic events, post traumatic stress disorder (PTSD), cultural identification, percent Native American Heritage, substance dependence, affective/anxiety disorders, and conduct disorder/antisocial personality disorder (ASPD). METHODS Participants were American Indians recruited from reservations that were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA), The Historical Loss Scale and The Historical Loss Associated Symptoms Scale (to quantify frequency of thoughts and symptoms of historical loss) the Stressful-Life-Events Scale (to assess experiences of trauma) and the Orthogonal Cultural Identification Scale (OCIS). RESULTS Three hundred and six (306) American Indian adults participated in the study. Over half of them indicated that they thought about historical losses at least occasionally, and that it caused them distress. Logistic regression revealed that significant increases in how often a person thought about historical losses were associated with: not being married, high degrees of Native Heritage, and high cultural identification. Additionally, anxiety/affective disorders and substance dependence were correlated with historical loss associated symptoms. CONCLUSIONS In this American Indian community, thoughts about historical losses and their associated symptomatology are common and the presence of these thoughts are associated with Native American Heritage, cultural identification, and substance dependence.
Collapse
Affiliation(s)
- Cindy L. Ehlers
- Molecular and Cellular Neurosciences Department, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Ian R. Gizer
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - David A. Gilder
- Molecular and Cellular Neurosciences Department, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jarrod M. Ellingson
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Rachel Yehuda
- James J. Peters Veterans Affairs Medical Center and Traumatic Stress Studies Division, Psychiatry Department, Mount Sinai School of Medicine, Bronx, NY 10029-6574, USA
| |
Collapse
|
5
|
Gizer IR, Gilder DA, Lau P, Wang T, Wilhelmsen KC, Ehlers CL. Contributions of ethnicity to differential item functioning of cannabis abuse and dependence symptoms. J Stud Alcohol Drugs 2013; 74:320-8. [PMID: 23384380 PMCID: PMC3568170 DOI: 10.15288/jsad.2013.74.320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 11/08/2012] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Cannabis is the most widely used illicit drug in the United States, and as a result, it is associated with significant public health costs. The present study sought to investigate whether item response theory (IRT) methods could be used to identify meaningful differences in how cannabis abuse and dependence symptoms (determined by criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) function as indices of the severity of misuse across two ethnic groups: Native Americans and European Americans. METHOD Participants were drawn from two previously collected samples, a population of Native Americans living on contiguous reservations (n = 406) and the University of California at San Francisco Family Alcoholism Study (n = 728). Cannabis use disorder symptoms were assessed using the Semi-Structured Assessment for the Genetics of Alcoholism. RESULTS Exploratory factor analysis demonstrated that the cannabis abuse and dependence symptoms indexed a single latent trait measuring severity of cannabis use. IRT and multiple indicators multiple causes (MIMIC) analyses suggested meaningful differences in the functioning of these symptoms across ethnic groups. Withdrawal represented a more prevalent and less severe symptom among Native Americans relative to European Americans, whereas each of the cannabis abuse symptoms and a symptom assessing psychological and health problems resulting from cannabis use were less prevalent but more severe in Native Americans. CONCLUSIONS The findings suggest differences in how cannabis use disorders manifest in these populations and thus have implications for the assessment of these disorders as well as theories attempting to explain the increased rates of substance use diagnoses more generally among Native Americans living on reservations.
Collapse
Affiliation(s)
- Ian R Gizer
- Department of Psychological Sciences, University of Missouri, Columbia, Missouri, USA.
| | | | | | | | | | | |
Collapse
|
6
|
Ehlers CL, Gizer IR, Gilder DA, Yehuda R. Lifetime history of traumatic events in an American Indian community sample: heritability and relation to substance dependence, affective disorder, conduct disorder and PTSD. J Psychiatr Res 2013; 47:155-61. [PMID: 23102628 PMCID: PMC3530021 DOI: 10.1016/j.jpsychires.2012.10.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 08/22/2012] [Accepted: 10/02/2012] [Indexed: 11/28/2022]
Abstract
American Indians appear to experience a higher rate of traumatic events than what has been reported in general population surveys. American Indians also suffer higher alcohol related death rates than any other ethnic group in the U.S. population. Therefore efforts to delineate factors which may uniquely contribute to increased likelihood of trauma, post traumatic stress disorder (PTSD), and substance use disorders (SUD) over the lifetime in American Indians are important because of the high burden of morbidity and mortality that they pose to American Indian communities. Participants were American Indians recruited from reservations that were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA), family history assessment and the stressful-life-events scale. Of the 309 participants, equivalent numbers of men and women (94%) reported experiencing traumas; however, a larger proportion of women received a PTSD diagnosis (38%) than men (29%). Having experienced multiple trauma and sexual abuse were most highly associated with PTSD. Having experienced assaultive trauma and having PTSD symptoms were both found to be moderately heritable (30-50%). Logistic regression revealed that having an anxiety and/or affective disorder and having a substance dependent diagnosis, but not having antisocial personality disorder/conduct disorder, were significantly correlated with having a diagnosis of PTSD. These studies suggest that trauma is highly prevalent in this American Indian community, it is heritable, is associated with PTSD, affective/anxiety disorders and substance dependence. Additionally, trauma, PTSD and substance dependence appear to all co-emerge in early adulthood in this high-risk population.
Collapse
Affiliation(s)
- Cindy L. Ehlers
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, CA 92037, USA,Corresponding author: Dr. Cindy.L. Ehlers, TSRI, 10550 North Torrey Pines Road SP30-1501, La Jolla, CA 92037 USA, Telephone: (858) 784-7058; Fax: (858) 784-7409;
| | - Ian R. Gizer
- Department of Psychological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - David A. Gilder
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Rachael Yehuda
- James J. Peters Veterans Affairs Medical Center and Traumatic Stress Studies Division, Psychiatry Department, Mount Sinai School of Medicine, Bronx, NY 10029-6574, USA
| |
Collapse
|
7
|
Conditional substance abuse and dependence by diagnosis of mood or anxiety disorder or schizophrenia in the U.S. population. Drug Alcohol Depend 2011; 119:28-36. [PMID: 21641123 PMCID: PMC3179836 DOI: 10.1016/j.drugalcdep.2011.05.010] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2010] [Revised: 05/05/2011] [Accepted: 05/08/2011] [Indexed: 11/22/2022]
Abstract
BACKGROUND Little is known about the association of various psychiatric disorders with the risk of developing dependence or abuse among users of various psychoactive substances (conditional dependence, CD; conditional abuse, CA). OBJECTIVES Evaluate the association of psychiatric disorders with CA only, CD only and CA+CD. METHOD Secondary analysis of data from 43,093 non-institutionalized US adults in the first wave (2001-2002) of the National Epidemiological Survey on Alcohol and Related Conditions. A structured diagnostic interview allowed classification by lifetime psychiatric diagnosis (DSM-IV criteria) and psychoactive substance use. Data were analyzed using weighted proportions, 95% CIs, and weighted logistic regression models to generate odds ratios (OR) adjusted for socio-demographic characteristics. RESULTS Psychiatric disorders were associated with higher prevalence of psychoactive substance use, regardless of type of disorder or substance. CA, CD and CA+CD prevalence rates were generally higher than unconditional prevalence rates among respondents with and without psychiatric disorders. Respondents with multiple disorders (mainly mood and anxiety disorders) had higher rates of CA+CD on most, but not all, psychoactive substances (e.g., not heroin), while schizophrenia was associated only with higher rates of tranquilizer CA+CD. Psychiatric disorders had few associations with CA only and CD only on psychoactive substances. CONCLUSION Study findings suggest that mood and anxiety disorders are associated with increased prevalence of substance use and increased transition from use to CA and CD, while schizophrenia is associated with increased transition from abstinence to use, especially for marijuana. Findings did not support the self-medication hypothesis of substance use disorders.
Collapse
|
8
|
Ehlers CL, Gizer IR, Gilder DA, Wilhelmsen KC. Linkage analyses of stimulant dependence, craving, and heavy use in American Indians. Am J Med Genet B Neuropsychiatr Genet 2011; 156B:772-80. [PMID: 21812097 PMCID: PMC3188982 DOI: 10.1002/ajmg.b.31218] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 06/30/2011] [Indexed: 11/06/2022]
Abstract
Amphetamine-type substances are the second most widely used illicit drugs in the United States. There is evidence to suggest that stimulant use (cocaine and methamphetamine) has a heritable component, yet the areas of the genome underlying these use disorders are yet to be identified. This study's aims were to map loci linked to stimulant dependence, heavy use, and craving in an American Indian community at high risk for substance dependence. DSM diagnosis of stimulant dependence, as well as indices of stimulant "craving," and "heavy use," were obtained using the Semi-Structured Assessment for the Genetics of Alcoholism (SSAGA). Genotypes were determined for a panel of 791 microsatellite polymorphisms in 381 members of multiplex families using SOLAR. Stimulant dependence, stimulant "craving," and "heavy stimulant use," were all found to be heritable. Analyses of multipoint variance component LOD scores, failed to yield evidence of linkage for stimulant dependence. For the stimulant "craving" phenotype, linkage analysis revealed a locus that had a LOD score of 3.02 on chromosome 15q25.3-26.1 near the nicotinic receptor gene cluster. A LOD score of 2.05 was found at this same site for "heavy stimulant use." Additional loci with LOD scores above 2.00 were found for stimulant "craving" on chromosomes 12p13.33-13.32 and 18q22.3. These results corroborate the importance of "craving" as an important phenotype that is associated with regions on chromosome 12, 15, and 18, that have been highlighted in prior segregation studies in this and other populations for substance dependence-related phenotypes.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Molecular and Integrative Neurosciences Department, The Scripps Research Institute, La Jolla, CA.
| | | | | | | |
Collapse
|
9
|
Abstract
OBJECTIVE This study's aims were to map loci linked to self-rating of the effects of alcohol and to determine if there was overlap with loci mapped earlier for other substance dependence phenotypes in an American Indian community at high risk for substance dependence. METHODS Each participant gave a blood sample and completed a structured diagnostic interview using the Semi Structured Assessment for the Genetics of Alcoholism. Retrospective report of responses to alcohol during the FIRST FIVE TIMES they had ever drank alcohol was estimated from the Self-Rating of the Effects of Alcohol (SRE) questionnaire for each participant. Genotypes were determined for a panel of 791 micro-satellite polymorphisms in 381 members of multiplex families using SOLAR. RESULTS Analyses of multipoint variance component Log of Odds (LOD) scores, for the FIRST FIVE TIMES phenotype, revealed two loci that had a LOD score greater than 3.0 on chromosomes 6 and 9. In addition, three locations were identified with LOD scores above 2.0 on chromosomes 10, 12, 17. CONCLUSION These results corroborate the importance of regions on chromosome 6 and 9 highlighted in earlier segregation studies in this and other populations for substance dependence-related phenotypes, as well as an area on chromosome 10 earlier identified for the FIRST FIVE TIMES phenotype in the collaborative study on the genetics of alcoholism. These studies additionally lend further support the construct that the SRE may represent an important endophenotype associated with alcohol and other substance dependence.
Collapse
|
10
|
Ehlers CL, Gizer IR, Phillips E, Wilhelmsen KC. EEG alpha phenotypes: linkage analyses and relation to alcohol dependence in an American Indian community study. BMC MEDICAL GENETICS 2010; 11:43. [PMID: 20298578 PMCID: PMC2851592 DOI: 10.1186/1471-2350-11-43] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 03/18/2010] [Indexed: 11/10/2022]
Abstract
BACKGROUND Evidence for a high degree of heritability of EEG alpha phenotypes has been demonstrated in twin and family studies in a number of populations. However, information on linkage of this phenotype to specific chromosome locations is still limited. This study's aims were to map loci linked to EEG alpha phenotypes and to determine if there was overlap with loci previously mapped for alcohol dependence in an American Indian community at high risk for substance dependence. METHODS Each participant gave a blood sample and completed a structured diagnostic interview using the Semi Structured Assessment for the Genetics of Alcoholism. Bipolar EEGs were collected and spectral power determined in the alpha (7.5-12.0 Hz) frequency band for two composite scalp locations previously identified by principal components analyses (bilateral fronto-central and bilateral centro-parietal-occipital). Genotypes were determined for a panel of 791 micro-satellite polymorphisms in 410 members of multiplex families using SOLAR. RESULTS Sixty percent of this study population had a lifetime diagnosis of alcohol dependence. Analyses of multipoint variance component LOD scores, for the EEG alpha power phenotype, revealed two loci that had a LOD score of 3.0 or above for the fronto-central scalp region on chromosomes 1 and 6. Additionally, 4 locations were identified with LOD scores above 2.0 on chromosomes 4, 11, 14, 16 for the fronto-central location and one on chromosome 2 for the centro-parietal-occipital location. CONCLUSION These results corroborate the importance of regions on chromosome 4 and 6 highlighted in prior segregation studies in this and other populations for alcohol dependence-related phenotypes, as well as other areas that overlap with other substance dependence phenotypes identified in previous linkage studies in other populations. These studies additionally support the construct that EEG alpha recorded from fronto-central scalp areas may represent an important endophenotype associated with alcohol and other substance dependence.
Collapse
Affiliation(s)
- Cindy L Ehlers
- From the Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA 92037, USA
- Molecular and Experimental Medicine, The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA 92037, USA
| | - Ian R Gizer
- Department of Genetics, University of North Carolina at Chapel Hill, 120 Mason Farm Road Room 5015 Genetic Medicine Building CB 7264, Chapel Hill, NC 27599-7264, USA
| | - Evelyn Phillips
- From the Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, 10550 North Torrey Pines Rd., SP30-1501, La Jolla, CA 92037, USA
| | - Kirk C Wilhelmsen
- Department of Genetics, University of North Carolina at Chapel Hill, 120 Mason Farm Road Room 5015 Genetic Medicine Building CB 7264, Chapel Hill, NC 27599-7264, USA
- Department of Neurology, The Carolina Center for Genome Sciences and the Bowles Center for Alcohol Studies, University of North Carolina, 4109 Neurosciences Research Bldg, CB#7264, Chapel Hill, NC 27599-7264, USA
| |
Collapse
|
11
|
Ehlers CL, Gizer IR, Vieten C, Gilder DA, Stouffer GM, Lau P, Wilhelmsen KC. Cannabis dependence in the San Francisco Family Study: age of onset of use, DSM-IV symptoms, withdrawal, and heritability. Addict Behav 2010; 35:102-10. [PMID: 19818563 DOI: 10.1016/j.addbeh.2009.09.009] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 07/31/2009] [Accepted: 09/03/2009] [Indexed: 11/15/2022]
Abstract
Cannabis is the most widely used illicit drug in the United States, yet the role of genetics in individual symptoms associated with cannabis use disorders has not been evaluated. The purpose of the present set of analyses was to describe the symptomatology and estimate the heritability of DSM-IV criteria/symptoms of cannabis dependence in a large sample of families. Participants were 2524 adults, participating in the University of California San Francisco (UCSF) Family Study of alcoholism. Seventy percent of the sample had ever used cannabis and 13.9% met DSM-IV criteria for cannabis dependence. Younger age at first cannabis use was found to be significantly associated with a shortened survival to becoming cannabis dependent. Although a greater percentage of men met criteria for cannabis dependence, women were found to demonstrate "telescoping" as indexed by a shorter survival time from initial use to dependence as compared to men. A cannabis withdrawal syndrome was identified in users, the primary symptoms of which were nervousness, appetite change, and sleep disturbance. Cannabis use (h(2)=0.31) and dependence (h(2)=0.20), age at first use, individual DSM-IV criteria for dependence, and cannabis-use associated symptoms of depression, trouble concentrating and paranoia were all found to be heritable. These findings suggest that within this population that cannabis use and dependence, as well as individual cannabis dependence symptoms have a significant heritable component, that cannabis dependence is more likely to occur when use begins during adolescence, and that the cannabis dependence syndrome includes a number of heritable untoward psychiatric side effects including withdrawal.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, 10550 North Torrey Pines Road, SP30-1501, La Jolla, CA 92037, USA.
| | | | | | | | | | | | | |
Collapse
|
12
|
Ehlers CL, Phillips E, Gizer IR, Gilder DA, Wilhelmsen KC. EEG spectral phenotypes: heritability and association with marijuana and alcohol dependence in an American Indian community study. Drug Alcohol Depend 2010; 106:101-10. [PMID: 19748744 PMCID: PMC2815012 DOI: 10.1016/j.drugalcdep.2009.07.024] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Revised: 07/21/2009] [Accepted: 07/22/2009] [Indexed: 11/30/2022]
Abstract
Native Americans have some of the highest rates of marijuana and alcohol use and abuse, yet neurobiological measures associated with dependence on these substances in this population remain unknown. The present investigation evaluated the heritability of spectral characteristics of the electroencephalogram (EEG) and their correlation with marijuana and alcohol dependence in an American Indian community. Participants (n=626) were evaluated for marijuana (MJ) and alcohol (ALC) dependence, as well as other psychiatric disorders. EEGs were collected from six cortical sites and spectral power determined in five frequency bands (delta 1.0-4.0 Hz, theta 4.0-7.5 Hz, alpha 7.5-12.0 Hz, low beta 12.0-20.0 Hz and high beta/gamma 20-50 Hz). The estimated heritability (h(2)) of the EEG phenotypes was calculated using SOLAR, and ranged from 0.16 to 0.67. Stepwise linear regression was used to detect correlations between MJ and ALC dependence and the spectral characteristics of the EEG using a model that took into account: age, gender, Native American Heritage (NAH) and a lifetime diagnosis of antisocial personality and/or conduct disorder (ASPD/CD). Increases in spectral power in the delta frequency range, were significantly correlated with gender (p<0.001) and marijuana dependence (p<0.003). Gender, age, NAH and ASPD/CD were all significantly (p<0.001) correlated with theta, alpha and beta band power, whereas alcohol dependence (p<0.01), gender (p<0.001), and ASPD/CD (p<0.001) were all correlated with high beta/gamma band power. These data suggest that the traits of EEG delta and high beta/gamma activity are correlated with MJ dependence and alcohol dependence, respectively, in this community sample of Native Americans.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | | | | | | | |
Collapse
|
13
|
Johnson BA, Elkashef AM, Seneviratne C, Ait-Daoud N, Kahn RC, Li SH, Bloch DA, Holmes TH, Wang XQ, Vocci FJ, Li MD. Association between Genotype of the Serotonin Transporter-Linked Polymorphic Region of the Serotonin Transporter Gene and Age of Onset of Methamphetamine Use: a Preliminary Analysis. Front Psychiatry 2010; 1:145. [PMID: 21423453 PMCID: PMC3059661 DOI: 10.3389/fpsyt.2010.00145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2010] [Accepted: 10/08/2010] [Indexed: 02/04/2023] Open
Abstract
Early-onset methamphetamine use increases the lifetime prevalence of methamphetamine dependence. An earlier onset of methamphetamine use leads to greater damage to the terminal ends of serotonin neurons, more reduction in serotonin transporter (5-HTT) density, and an increased propensity toward further methamphetamine use. Because the 5-HTT-linked polymorphic region (5'-HTTLPR) within the promoter region of the 5-HTT gene leads to differential expression of the 5-HTT, we examined, for the first time, whether there is a differential association between the long (L) and short (S) alleles of the 5'-HTTLPR and the age of first methamphetamine use (AMU). The study included 120 methamphetamine-dependent adults of European descent. Diagnosis of methamphetamine dependence and AMU were collected using structured questionnaires, and the 5'-HTTLPR genotypes were determined using the polymerase chain reaction-restriction fragment length polymorphism method. Statistical analysis with the general linear model detected a significant interactive effect of 5'-HTTLPR genotypes (SS vs. L-carriers) and gender, associated with AMU (F = 3.99; p = 0.048). Further analysis of 5'-HTTLPR effects on AMU in males and females separately showed that the SS genotype compared with L-carriers had about two times greater risk of an earlier onset of methamphetamine use in men (hazard ratio = 1.839; 95% confidence interval = 1.042-3.246; p = 0.036) but not in women. Together, our findings in this preliminary study suggest a greater risk for earlier onset methamphetamine use associated with the SS genotype of the 5'-HTTLPR among methamphetamine-dependent Caucasian males.
Collapse
Affiliation(s)
- Bankole A Johnson
- Department of Psychiatry and Neurobehavioral Sciences, University of Virginia Charlottesville, VA, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Ehlers CL, Gilder DA, Gizer IR, Wilhelmsen KC. Heritability and a genome-wide linkage analysis of a Type II/B cluster construct for cannabis dependence in an American Indian community. Addict Biol 2009; 14:338-48. [PMID: 19413562 DOI: 10.1111/j.1369-1600.2009.00160.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Subtyping of substance dependence disorders holds promise for a number of important research areas including phenotyping for genetic studies, characterizing clinical course, and matching treatment and prevention strategies. This study sought to investigate whether a dichotomous construct similar to Babor's Types A/B and Cloninger's Types I/II for alcohol dependence can be identified for cannabis dependence in a Native American sample. In addition, heritability of this construct and its behavior in a genetic linkage analyses were evaluated. Information on cannabis use and dependence symptoms and other psychiatric disorders was obtained using the Semi-Structured Assessment for the Genetics of Alcoholism from a community sample of 606 American Indians. Hierarchical average linkage and K means cluster analysis was used, and a three-cluster solution was found to generate the best separation of variables. Ninety-one per cent of cannabis-dependent participants fell into one of the two subtypes: Type A/I cluster (n = 114, 56%) and Type B/II cluster (n = 70, 35%). Heritability (estimated using Sequential Oligogenic Linkage Analysis Routines) was only significant for the Type B/II cluster (h(2) = 0.44, SE = 0.18, P < 0.01). Evidence for linkage was found for the Type B/II cluster (versus no diagnosis) on chromosome 16 [at 139 centimorgans (cM), Log of the Odds (LOD) score = 4.4], and on chromosome 19 (at 74 cM, LOD score = 6.4). Regions of interest for this phenotype (LOD > 1.5) were also located on chromosomes 14, 21, 22. These findings suggest that a Type B/II cannabis dependence phenotype can be identified in this population and that it is in part heritable and linked to areas of the genome identified previously for drug dependence phenotypes in this population as well as in other studies.
Collapse
MESH Headings
- Adult
- Chromosomes, Human, Pair 14/genetics
- Chromosomes, Human, Pair 16/genetics
- Chromosomes, Human, Pair 19/genetics
- Chromosomes, Human, Pair 21/genetics
- Chromosomes, Human, Pair 22/genetics
- Cluster Analysis
- Cross-Sectional Studies
- Female
- Genetic Linkage/genetics
- Genome-Wide Association Study
- Humans
- Indians, North American/genetics
- Indians, North American/statistics & numerical data
- Lod Score
- Male
- Marijuana Abuse/classification
- Marijuana Abuse/epidemiology
- Marijuana Abuse/genetics
- Middle Aged
- Phenotype
- Risk Factors
- Substance-Related Disorders/classification
- Substance-Related Disorders/genetics
- Young Adult
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Integrative Neurosciences, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
| | | | | | | |
Collapse
|
15
|
Agrawal A, Lynskey MT. Are there genetic influences on addiction: evidence from family, adoption and twin studies. Addiction 2008; 103:1069-81. [PMID: 18494843 DOI: 10.1111/j.1360-0443.2008.02213.x] [Citation(s) in RCA: 249] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIMS In this exciting era of gene discovery, we review evidence from family, adoption and twin studies that examine the genetic basis for addiction. With a focus on the classical twin design that utilizes data on monozygotic and dizygotic twins, we discuss support in favor of heritable influences on alcohol, nicotine, cannabis and other illicit drug dependence. METHODS We review whether these genetic factors also influence earlier stages (e.g. experimentation) of the addictive process and whether there are genetic influences specific to each psychoactive substance. RESULTS Converging evidence from these studies supports the role of moderate to high genetic influences on addiction with estimates ranging from 0.30 to 0.70. The changing role of these heritable factors as a function of gender, age and cultural characteristics is also discussed. We highlight the importance of the interplay between genes and the environment as it relates to risk for addiction and the utility of the children-of-twins design for emerging studies of gene-environment interaction is presented. CONCLUSIONS Despite the advances being made by low-cost high-throughput whole genome association assays, we posit that information garnered from twin studies, especially extended twin designs with power to examine gene-environment interactions, will continue to form the foundation for genomic research.
Collapse
Affiliation(s)
- Arpana Agrawal
- Department of Psychiatry, Washington University School of Medicine, St Louis, MO 63110, USA.
| | | |
Collapse
|
16
|
Ehlers CL, Lind PA, Wilhelmsen KC. Association between single nucleotide polymorphisms in the mu opioid receptor gene (OPRM1) and self-reported responses to alcohol in American Indians. BMC MEDICAL GENETICS 2008; 9:35. [PMID: 18433502 PMCID: PMC2386778 DOI: 10.1186/1471-2350-9-35] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2007] [Accepted: 04/23/2008] [Indexed: 11/10/2022]
Abstract
BACKGROUND Variation in response to the hedonic and adverse effects of a substance is in part an inherited factor that may influence its use, abuse and dependence. The mu opioid receptor is the primary site of action for opiates and individuals with polymorphisms in this receptor appear to have variation in the CNS effects of opiates. Several studies have suggested that this receptor may also mediate some of the effects of non-opioid drugs, such as alcohol. The purpose of this study was to investigate associations between 13 single nucleotide polymorphisms in the mu opioid receptor gene (OPRM1) with self-reported responses to alcohol, an endophenotype associated with the development of alcohol dependence, in American Indians living on eight contiguous reservations. METHODS Each participant gave a blood sample and completed a structured diagnostic interview. Additionally, response to alcohol was indexed using the expectation version of the subjective high assessment scale (SHAS-E). SNPs were genotyped in 251 participants and data analyses were conducted using SOLAR. RESULTS The estimated heritability (h2) for the SHAS-E phenotypes ranged from 0.01 to 0.28. Endorsing the expectation of a more intense response on one or more of the following items from the SHAS-E: buzzed, clumsy, dizzy, drunk, effects, high, nausea, sleepy, talkative, terrible, and/or uncomfortable after imbibing 2-3 drinks was significantly associated with having at least one minor allele for at least one of 7 SNPs (p < 0.01) in the OPRM1 receptor gene. CONCLUSION These studies provide data to suggest that the minor allele, for most of the polymorphisms in the OPRM1 receptor gene investigated, was found to be associated with a more intense, and/or more adverse, response to alcohol, traits that are significantly correlated with lowered quantity of alcohol consumption and less susceptibility to dependence in this Indian population. These data further suggest that making conclusions on the role of the mu opiod receptor gene in the development of alcohol dependence may be limited if only one polymorphism in the gene is evaluated in isolation.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA, USA.
| | | | | |
Collapse
|
17
|
Ehlers CL, Gilder DA, Phillips E. P3 components of the event-related potential and marijuana dependence in Southwest California Indians. Addict Biol 2008; 13:130-42. [PMID: 18201292 DOI: 10.1111/j.1369-1600.2007.00091.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Native Americans have some of the highest rates of marijuana use and abuse, yet neurobiological measures associated with addiction to marijuana in this population remain unknown. The present investigation evaluated associations between the P350 and P450 components of the event-related potential (ERP) elicited by affective stimuli, and marijuana dependence in a population of Southwest California (SWC) Indian adults. Three hundred and seventeen participants with a mean age of 30 years who were free of major Axis I and psychiatric diagnoses and antisocial personality disorder were categorized as: (1) no marijuana use disorders or other drug dependence diagnoses; (2) marijuana dependence and no other drug dependence diagnoses; and (3) marijuana dependence and other drug dependence diagnoses. ERPs were collected using a facial discrimination task that generated a late positive component with two peaks at approximately P350 and P450 milliseconds. Multivariate analyses of variance was used to detect associations between the two component peaks and the three participant groups taking into consideration age, gender and the presence of a lifetime diagnosis of alcohol dependence. Increases in the latency of both the P350 and P450 component peaks were found to be associated with the diagnosis of marijuana dependence and marijuana dependence co-morbid with other drug dependence. Women appeared to be more impacted than men are. A diagnosis of marijuana dependence was not associated with any changes in late component amplitudes. Taken together these studies suggest that marijuana dependence may be associated with delays in the evaluation and identification of emotional stimuli in SWC Indians.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Integrative Neurosciences and Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | | | | |
Collapse
|
18
|
Ehlers CL, Slutske WS, Lind PA, Wilhelmsen KC. Association between single nucleotide polymorphisms in the cannabinoid receptor gene (CNR1) and impulsivity in southwest California Indians. Twin Res Hum Genet 2008; 10:805-11. [PMID: 18179391 DOI: 10.1375/twin.10.6.805] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Impulsivity is a personality trait characterized by acting suddenly in an unplanned manner in order to satisfy a desire without consideration for the consequences of such behavior. There are several psychiatric disorders that include the term impulsivity as a criterion and, therefore, it has been suggested that impulsivity may be an important phenotype that may link a number of different behavioral disorders, including substance abuse. This study's aims were to determine if a significant association could be detected between the (AAT)n triplet repeat polymorphism as well as 5 single nucleotide polymorphisms (SNPs) in or near the CNR1 receptor gene and impulsivity in Southwest California 'Mission' Indians (SWC). Impulsivity was assessed using a scale derived from the Maudsley personality inventory, and blood samples were collected for DNA analyses from 251 individuals recruited from local Indian reservations. The estimated heritability (h(2)) for the impulsivity phenotype was 0.20 + 0.12 (p < .004). Impulsivity was significantly associated with the 6-repeat allele of the triplet repeat polymorphism (AATn/A6; p < .0001), as well as four SNPs in or near the CNR1 receptor gene: rs1535255 (p = .001), rs2023239 (p = .004), rs1049353 (p < .001) and rs806368 (p < .0006). These studies provide data to suggest that the CNR1 receptor gene may be significantly associated with impulsivity in SWC Indians.
Collapse
Affiliation(s)
- Cindy L Ehlers
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA.
| | | | | | | |
Collapse
|