Alcohol Dependence Symptoms and Alcohol Dehydrogenase 2 Polymorphism: Israeli Ashkenazis, Sephardics, and Recent Russian Immigrants

Associations of ADH1B and ALDH2 genotypes and alcohol flushing with drinking history, withdrawal symptoms, and ICD-10 criteria in Japanese alcohol-dependent men

OBJECTIVES

Given the high prevalence of fast-metabolizing alcohol dehydrogenase-1B*2 (ADH1B*2 ) and inactive aldehyde dehydrogenase-2*2 (ALDH2*2 ) alleles in East Asians, we evaluated how the ADH1B / ALDH2 genotypes and alcohol flushing might affect the development of alcohol dependence (AD).

METHODS

We evaluated how the ADH1B / ALDH2 genotypes and self-reported alcohol flushing affected history of drinking events and withdrawal symptoms and ICD-10 criteria in 4116 Japanese AD men.

RESULTS

The ADH1B*1/*1 group and ALDH2*1/*1 group were 1-5 years younger than the ADH1B*2 (+) and ALDH2*1/*2 groups, respectively, for all of the ages at onset of habitual drinking, blackouts, daytime drinking, uncontrolled drinking, withdrawal symptoms, and first treatment for AD, and the current age. Blackouts were more common in the ADH1B*1/*1 group and ALDH2*1/*1 group. Daytime drinking, uncontrolled drinking, and withdrawal symptoms, such as hand tremor, sweating, convulsions, and delirium tremens/hallucinations were more common in the ADH1B*1/*1 group. The ADH1B*1/*1 was positively associated with the ICD-10 criteria for 'tolerance' and 'withdrawal symptoms'. The ADH1B*1/*1 group and ALDH2*1/*2 group had a larger ICD-10 score. Never flushing was reported by 91.7% and 35.2% of the ALDH2*1/*1 and ALDH2*1/*2 carriers, respectively. After a 1-2-year delay in the onset of habitual drinking in the former-/current-flushing group, no differences in the ages of the aforementioned drinking milestones were found according to the flushing status.

CONCLUSION

The ADH1B*1/*1 and ALDH2*1/*1 accelerated the development of drinking events and withdrawal symptoms in Japanese AD patients. ICD-10 score was larger in the ADH1B*1/*1 group and ALDH2*1/*2 group. The effects of alcohol flushing on drinking events were limited.

Association between polygenic risk for tobacco or alcohol consumption and liability to licit and illicit substance use in young Australian adults

BACKGROUND

Co-morbid substance use is very common. Despite a historical focus using genetic epidemiology to investigate comorbid substance use and misuse, few studies have examined substance-substance associations using polygenic risk score (PRS) methods.

METHODS

Using summary statistics from the largest substance use GWAS to date (258,797- 632,802 subjects), GWAS and Sequencing Consortium of Alcohol and Nicotine use (GSCAN), we constructed PRSs for smoking initiation (PRS-SI), age of initiation of regular smoking (PRS-AI), cigarettes per day (PRS-CPD), smoking cessation (PRS-SC), and drinks per week (PRS-DPW). We then estimated the fixed effect of individual PRSs on 22 lifetime substance use and substance use disorder phenotypes collected in an independent sample of 2463 young Australian adults using genetic restricted maximal likelihood (GREML) in Genome-wide Complex Trait Analysis (GCTA), separately in females, males and both sexes together.

RESULTS

After accounting for multiple testing, PRS-SI significantly explained variation in the risk of cocaine (0.67%), amphetamine (1.54%), hallucinogens (0.72%), ecstasy (1.66%) and cannabis initiation (0.97%), as well as DSM-5 alcohol use disorder (0.72%). PRS-DPW explained 0.75%, 0.59% and 0.90% of the variation of cocaine, amphetamine and ecstasy initiation respectively. None of the 22 phenotypes including emergent classes of substance use were significantly predicted by PRS-AI, PRS-CPD, and PRS-SC.

CONCLUSIONS

To our knowledge, this is the first study to report significant genetic overlap between the polygenic risks for smoking initiation and alcohol consumption and the risk of initiating major classes of illicit substances. PRSs constructed from large discovery GWASs allows the detection of novel genetic associations.

Alcohol Dehydrogenases, Aldehyde Dehydrogenases, and Alcohol Use Disorders: A Critical Review

Alcohol use disorders (AUDs) are complex traits, meaning that variations in many genes contribute to the risk, as does the environment. Although the total genetic contribution to risk is substantial, most individual variations make only very small contributions. By far the strongest contributors are functional variations in 2 genes involved in alcohol (ethanol [EtOH]) metabolism. A functional variant in alcohol dehydrogenase 1B (ADH1B) is protective in people of European and Asian descent, and a different functional variant in the same gene is protective in those of African descent. A strongly protective variant in aldehyde dehydrogenase 2 (ALDH2) is essentially only found in Asians. This highlights the need to study a wide range of populations. The likely mechanism of protection against heavy drinking and AUDs in both cases is alteration in the rate of metabolism of EtOH that at least transiently elevates acetaldehyde. Other ADH and ALDH variants, including functional variations in ADH1C, have also been implicated in affecting drinking behavior and risk for alcoholism. The pattern of linkage disequilibrium in the ADH region and the differences among populations complicate analyses, particularly of regulatory variants. This critical review focuses upon the ADH and ALDH genes as they affect AUDs.

Unmet need for treatment of depression among immigrants from the former USSR in the US: A primary care study

The stress of immigration can increase risk for major depressive disorder (MDD), while cultural factors can contribute to difficulty in diagnosis and treatment of MDD among immigrant populations. Consequently, immigrants are less likely to have their treatment needs met. Our goal was to assess the unmet need for the diagnosis and treatment of depression among immigrants from the former USSR-a large immigrant group in the US-as well as demographic characteristics and immigration history associated with depression. We conducted a survey in an urban primary care clinic using measures of MDD symptoms (Patient Health Questionnaire-9), functioning, and treatment history among 102 Russian-speaking immigrants. Current moderate-to-severe symptoms of MDD were reported by 26.5% of participants with 33.3% of the symptomatic patients reporting suicidal ideation. Among participants with probable MDD, 63.0% reported not receiving mental health treatment and 59.3% never being diagnosed with MDD. The rates of untreated depression did not vary by gender nor did they diminish with prolonged stay in the US. Results suggest that undiagnosed and untreated depression is highly prevalent in this immigrant group.

Oxidative and reductive metabolism of lipid-peroxidation derived carbonyls

Extensive research has shown that increased production of reactive oxygen species (ROS) results in tissue injury under a variety of pathological conditions and chronic degenerative diseases. While ROS are highly reactive and can incite significant injury, polyunsaturated lipids in membranes and lipoproteins are their main targets. ROS-triggered lipid-peroxidation reactions generate a range of reactive carbonyl species (RCS), and these RCS spread and amplify ROS-related injury. Several RCS generated in oxidizing lipids, such as 4-hydroxy trans-2-nonenal (HNE), 4-oxo-2-(E)-nonenal (ONE), acrolein, malondialdehyde (MDA) and phospholipid aldehydes have been shown to be produced under conditions of oxidative stress and contribute to tissue injury and dysfunction by depleting glutathione and other reductants leading to the modification of proteins, lipids, and DNA. To prevent tissue injury, these RCS are metabolized by several oxidoreductases, including members of the aldo-keto reductase (AKR) superfamily, aldehyde dehydrogenases (ALDHs), and alcohol dehydrogenases (ADHs). Metabolism via these enzymes results in RCS inactivation and detoxification, although under some conditions, it can also lead to the generation of signaling molecules that trigger adaptive responses. Metabolic transformation and detoxification of RCS by oxidoreductases prevent indiscriminate ROS toxicity, while at the same time, preserving ROS signaling. A better understanding of RCS metabolism by oxidoreductases could lead to the development of novel therapeutic interventions to decrease oxidative injury in several disease states and to enhance resistance to ROS-induced toxicity.

Childhood adversity moderates the effect of ADH1B on risk for alcohol-related phenotypes in Jewish Israeli drinkers

Childhood adversity and genetic variant ADH1B-rs1229984 have each been shown to influence heavy alcohol consumption and disorders. However, little is known about how these factors jointly influence these outcomes. We assessed the main and additive interactive effects of childhood adversity (abuse, neglect and parental divorce) and the ADH1B-rs1229984 on the quantitative phenotypes 'maximum drinks in a day' (Maxdrinks) and DSM-Alcohol Use Disorder (AUD) severity, adjusting for demographic variables, in an Israeli sample of adult household residents (n = 1143) evaluated between 2007 and 2009. Childhood adversity and absence of the protective ADH1B-rs1229984 A allele were associated with greater mean Maxdrinks (mean differences: 1.50; 1.13, respectively) and AUD severity (mean ratios: 0.71; 0.27, respectively). In addition, childhood adversity moderated the ADH1B-rs1229984 effect on Maxdrinks (P < 0.01) and AUD severity (P < 0.05), in that there was a stronger effect of ADH1B-rs1229984 genotype on Maxdrinks and AUD severity among those who had experienced childhood adversity compared with those who had not. ADH1B-rs1229984 impacts alcohol metabolism. Therefore, among those at risk for greater consumption, e.g. those who experienced childhood adversity, ADH1B-rs1229984 appears to have a stronger effect on alcohol consumption and consequently on risk for AUD symptom severity. Evidence for the interaction of genetic vulnerability and early life adversity on alcohol-related phenotypes provides further insight into the complex relationships between genetic and environmental risk factors.

Parental psychopathology moderates the influence of parental divorce on lifetime alcohol use disorders among Israeli adults

BACKGROUND

Parental divorce and psychopathology are well-documented risk factors for alcohol use disorders (AUD) in the United States and other countries where divorce is common and per capita total alcohol consumption is moderate to high. However, little is known about these relationships in countries where divorce and alcohol problems are less common, such as Israel.

METHODS

Israeli adult household residents (N=797) age 21-45 were interviewed in person between 2007 and 2009. Logistic regression models were used to examine main and additive interaction effects of parental divorce and psychopathology on lifetime DSM-IV AUD, adjusting for age, gender, and ethnicity.

RESULTS

Parental divorce (OR=2.18, p≤0.001) and parental psychopathology (OR=1.61, p≤0.01) were independently associated with lifetime AUD and, when considered together, showed significant interaction (p=0.026). Specifically, the effect of divorce on AUD was only significant among those who also reported parental psychopathology.

CONCLUSIONS

This is the first study showing the influence of parental divorce and psychopathology on risk for AUD among Israeli adults, where both divorce and AUD are less common than in the United States. Alcohol prevention and treatment professionals should recognize that children who experience parental divorce and/or psychopathology could be more vulnerable to later developing AUD than those whose parents remain together and without psychopathology.

Jewish mortality reconsidered

It is known that mortality of Jews is different from the mortality of the populations that surround them. However, the existence of commonalities in mortality of different Jewish communities across the world has not received scholarly attention. This paper aims to identify common features of the evolution of Jewish mortality among Jews living in Israel and the Diaspora. In the paper the mortality of Jews in Israel is systematically compared with the mortality of the populations of developed countries, and the findings from the earlier studies of mortality of Jews in selected Diaspora communities are re-examined. The outcome is a re-formulation and extension of the notion of the 'Jewish pattern of mortality'. The account of this pattern is based on the consistently low level of behaviourally induced mortality, the migration history of Jewish populations and the enduring influence of early-life conditions on mortality at older ages.

Comparison of categorical alcohol dependence versus a dimensional measure for predicting weekly alcohol use in heavy drinkers

BACKGROUND

The DSM specifies categorical criteria for psychiatric disorders. In contrast, a dimensional approach considers variability in symptom severity and can significantly improve statistical power. The current study tested whether a categorical, DSM-defined diagnosis of Alcohol Dependence (AD) was a better fit than a dimensional dependence measure for predicting change in alcohol consumption among heavy drinkers following a brief alcohol intervention (BI). DSM-IV and DSM-5 alcohol use disorder (AUD) measures were also evaluated.

METHODS

Participants (N=246) underwent a diagnostic interview after receiving a BI, then reported daily alcohol consumption using an Interactive Voice Response system. Dimensional AD was calculated by summing the dependence criteria (mean=4.0; SD=1.8). The dimensional AUD measure was a summation of positive Alcohol Abuse plus AD criteria (mean=5.8; SD=2.5). A multi-model inference technique was used to determine whether the DSM-IV categorical diagnosis or dimensional approach would provide a more accurate prediction of first week consumption and change in weekly alcohol consumption following a BI.

RESULTS

The Akaike information criterion (AIC) for the dimensional AD model (AIC=7625.09) was 3.42 points lower than the categorical model (AIC=7628.51) and weight of evidence calculations indicated there was 85% likelihood that the dimensional model was the better approximating model. Dimensional AUD models fit similarly to the dimensional AD model. All AUD models significantly predicted change in alcohol consumption (p's=.05).

CONCLUSION

A dimensional AUD diagnosis was superior for detecting treatment effects that were not apparent with categorical and dimensional AD models.

Alcohol dependence and suicide-related ideation/behaviors in an Israeli household sample, with and without major depression

BACKGROUND

Suicide-related ideation and behaviors (SRIB) are associated with both alcohol disorders and major depressive disorder (MDD). The objective of this study was to evaluate the relationship of alcohol dependence (AD) and major depression to the risk for lifetime SRIB.

METHODS

Data from a community-based sample of 1,237 adult Israeli lifetime drinkers assessed with reliable diagnostic measures were analyzed using logistic regression.

RESULTS

Lifetime SRIB was reported in 4.7% and was more prevalent among participants with AD (9.0%) than among those without AD (4.1%); p-value = 0.01. Although both AD and major depression were associated with SRIB (AD: OR 2.2, 95% CI 1.1 to 4.4; MDD: OR 11.4, 95% CI = 6.4 to 20.4), joint analysis showed that AD without MDD increased risk for SRIB as compared to those without AD or MDD (OR 3.1, 95% CI 1.1 to 9.1), but AD did not increase risk among those with MDD (OR 1.1, 95% CI 0.4 to 2.7). Among those with AD, the severity of subclinical depressive symptoms was associated with increased SRIB.

CONCLUSIONS

These findings show that AD increases risk for SRIB among individuals without a history of major depression. Suicidal tendencies may be undetected and underdiagnosed in this group because of the absence of major depression and therefore left untreated. These findings should be considered when adopting suicide prevention or treatment strategies for this high-risk subpopulation.

Alcohol-metabolizing genes and alcohol phenotypes in an Israeli household sample

BACKGROUND

Alcohol dehydrogenase 1B and 1C (ADH1B and ADH1C) variants have been robustly associated with alcohol phenotypes in East Asian populations, but less so in non-Asian populations where prevalence of the most protective ADH1B allele is low (generally <5%). Further, the joint effects of ADH1B and ADH1C on alcohol phenotypes have been unclear. Therefore, we tested the independent and joint effects of ADH1B and ADH1C on alcohol phenotypes in an Israeli sample, with higher prevalence of the most protective ADH1B allele than other non-Asian populations.

METHODS

A structured interview assessed lifetime drinking and alcohol use disorders (AUDs) in adult Israeli household residents. Four single nucleotide polymorphisms (SNPs) were genotyped: ADH1B (rs1229984, rs1229982, and rs1159918) and ADH1C (rs698). Regression analysis examined the association between alcohol phenotypes and each SNP (absence vs. presence of the protective allele) as well as rs698/rs1229984 diplotypes (also indicating absence or presence of protective alleles) in lifetime drinkers (n = 1,129).

RESULTS

Lack of the ADH1B rs1229984 protective allele was significantly associated with consumption- and AUD-related phenotypes (OR = 1.77 for AUD; OR = 1.83 for risk drinking), while lack of the ADH1C rs698 protective allele was significantly associated with AUD-related phenotypes (OR = 2.32 for AUD). Diplotype analysis indicated that jointly ADH1B and ADH1C significantly influenced AUD-related phenotypes. For example, among those without protective alleles for ADH1B or ADH1C, OR for AUD was 1.87 as compared to those without the protective allele for ADH1B only and was 3.16 as compared to those with protective alleles for both ADH1B and ADH1C.

CONCLUSIONS

This study adds support for the relationship of ADH1B and ADH1C and alcohol phenotypes in non-Asians. Further, these findings help clarify the mixed results from previous studies by showing that ADH1B and ADH1C jointly effect AUDs, but not consumption. Studies of the association between alcohol phenotypes and either ADH1B or ADH1C alone may employ an oversimplified model, masking relevant information.

Joint toxicity of alkoxyethanol mixtures: contribution of in silico applications

Exposure to chemicals occurs often as mixtures. Presented in this paper is information on alkoxyethanols and the impact they might have on human health in combination with some commonly found aliphatic and aromatic compounds. Our studies to evaluate the joint toxicity of these chemicals among themselves and in combination with other chemicals reveal a variety of possible outcomes depending on the exposure scenario. The interactions are predominantly based on metabolic pathways and are common among several solvents and organic compounds. Quantitative structure activity relationship (QSAR) analysis can be used with high confidence to identify chemicals that will interact to influence overall joint toxicity. Potential human exposure to a combination of alkoxyethanol, toluene and substituted benzenes may increase reproductive and developmental disease conditions. Inheritable gene alterations result in changes in the enzyme function in different subpopulations causing variations in quantity and/or quality of particular isoenzymes. These changes are responsible for differential metabolism of chemicals in species, genders, and life stages and are often the basis of a population's susceptibility. Unique genotypes introduced as a function of migration can alter the genetic makeup of any given population. Hence special consideration should be given to susceptible populations while conducting chemical health risk assessments.

High school students' posttraumatic symptoms, substance abuse and involvement in violence in the aftermath of war

This study examined one-year after effects of exposure to war events on adolescents' Posttraumatic Stress Symptoms (PTS) and risk behaviors (substance use and involvement in school violence). In addition, it addressed two potential vulnerability factors: at the micro level, it examined whether childhood trauma raised the vulnerability of Israeli adolescents to PTS and risk behaviors when exposed to war events. At the macro level, we explored whether ethnicity, i.e., being an Israeli Arab, is a vulnerability factor to PTS and risk behaviors. We used a representative sample of 7th to 11th grade students from the north of Israel that included 4151 students: 1800 Jewish (54.4% boys) and 2351 Arab (41.5% boys). We assessed exposure to war events and childhood traumatic events, PTS and PTSD, substance use (alcohol, cannabis, Ecstasy) and involvement in school violence. The findings revealed extensive exposure to war events among both Jewish and Arab students. A year after the war, its effects on adolescents were still manifested in PTS, and involvement in school violence and substance use. Exposure to child physical abuse was associated with higher levels of PTS symptoms, substance use and involvement in violence. Exposure to other traumatic events was also associated with greater PTS symptoms and involvement in violence but not with greater substance use. Arab students were a more vulnerable population. They reported higher PTS symptoms, more cannabis use and greater involvement in school violence than Jewish students. However, exposure to war events had similar effects on both Arab and Jewish students. We conclude that war effects include a broad range of psychological distress and risk behaviors that last long after the war ends, especially among youth who have experienced childhood trauma and high exposure to war-related stressors.

Suicidal behavior among immigrants

INTRODUCTION

This paper explores the association between suicidal behavior and immigrant status among Israeli residents from the former USSR (FSU).

METHOD

The Israeli component of the World Mental Health Survey (INHS) provided information on suicide ideations, plans and attempts. The INHS samples included Israel-born Jews (n = 2,114) and post-1990 immigrants from the FSU (n = 814). Data on completed suicide were extracted from the countrywide report of the Ministry of Health.

RESULTS

The controlled lifetime rates of suicidal behavior among FSU immigrants were significantly higher than among their Israel-born counterparts. A higher risk was found in the first years following immigration among young adults with higher education and without a spouse. Completed suicide rates were higher among the FSU immigrants than in the general Israeli population with the largest risk among young-adult immigrant men.

DISCUSSION

The findings are consistent with previous studies and are discussed in the context of both suicide rates in the country of origin and migratory stressors. Preventive measures are suggested.

Nicotine dependence, abuse and craving: dimensionality in an Israeli sample

AIMS

Evidence-based changes planned for Diagnostic and Statistical Manual 5th edition (DSM-5) substance use disorders (SUDs) include combining dependence and three of the abuse criteria into one disorder and adding a criterion indicating craving. Because DSM-IV did not include a category for nicotine abuse, little empirical support is available for aligning the nicotine use disorder criteria with the DSM-5 criteria for other SUDs.

DESIGN

Latent variable analyses, bootstrap tests and likelihood ratio tests were used to explore the unidimensionality, psychometric properties and information of the nicotine criteria.

SETTING AND PARTICIPANTS

A sample of household residents selected from the Israeli population register yielded 727 life-time cigarette smokers.

MEASUREMENTS

DSM-IV nicotine dependence criteria and proposed abuse and craving criteria, assessed with a structured interview.

FINDINGS

Three abuse criteria (hazardous use, social/interpersonal problems and neglect roles) were prevalent among smokers, formed a unidimensional latent trait with nicotine dependence criteria, were intermixed with dependence criteria across the severity spectrum and significantly increased the diagnostic information over the dependence-only model. A craving criterion was shown to fit well with the other criteria.

CONCLUSION

Similar to findings from research on other substances, nicotine dependence, abuse and craving criteria appear to derive from a common underlying dimension. The results support alignment of nicotine criteria with those for alcohol and drug use disorders in Diagnostic and Statistical Manual 5th edition.

Ethanol metabolism by HeLa cells transduced with human alcohol dehydrogenase isoenzymes: control of the pathway by acetaldehyde concentration

BACKGROUND

Human class I alcohol dehydrogenase 2 isoenzymes (encoded by the ADH1B locus) have large differences in kinetic properties; however, individuals inheriting the alleles for the different isoenzymes exhibit only small differences in alcohol elimination rates. This suggests that other cellular factors must regulate the activity of the isoenzymes.

METHODS

The activity of the isoenzymes expressed from ADH1B*1, ADH1B*2, and ADH1B*3 cDNAs was examined in stably transduced HeLa cell lines, including lines which expressed human low K(m) aldehyde dehydrogenase (ALDH2). The ability of the cells to metabolize ethanol was compared with that of HeLa cells expressing rat class I alcohol dehydrogenase (ADH) (HeLa-rat ADH cells), rat hepatoma (H4IIEC3) cells, and rat hepatocytes.

RESULTS

The isoenzymes had similar protein half-lives in the HeLa cells. Rat hepatocytes, H4IIEC3 cells, and HeLa-rat ADH cells oxidized ethanol much faster than the cells expressing the ADH1B isoenzymes. This was not explained by high cellular NADH levels or endogenous inhibitors; but rather because the activity of the β1 and β2 ADHs was constrained by the accumulation of acetaldehyde, as shown by the increased rate of ethanol oxidation by cell lines expressing β2 ADH plus ALDH2.

CONCLUSION

The activity of the human β2 ADH isoenzyme is sensitive to inhibition by acetaldehyde, which likely limits its activity in vivo. This study emphasizes the importance of maintaining a low steady-state acetaldehyde concentration in hepatocytes during ethanol metabolism.

Association of alcohol dehydrogenase genes with alcohol-related phenotypes in a Native American community sample

BACKGROUND

Previous linkage studies, including a study of the Native American population described in the present report, have provided evidence for linkage of alcohol dependence and related traits to chromosome 4q near a cluster of alcohol dehydrogenase (ADH) genes, which encode enzymes of alcohol metabolism.

METHODS

The present study tested for associations between alcohol dependence and related traits and 22 single-nucleotide polymorphisms (SNPs) spanning the 7 ADH genes. Participants included 586 adult men and women recruited from 8 contiguous Native American reservations. A structured interview was used to assess DSM-III-R alcohol dependence criteria as well as a set of severe alcohol misuse symptoms and alcohol withdrawal symptoms.

RESULTS

No evidence for association with the alcohol dependence diagnosis was observed, but an SNP in exon 9 of ADH1B (rs2066702; ADH1B*3) and an SNP at the 5' end of ADH4 (rs3762894) showed significant evidence of association with the presence of withdrawal symptoms (p = 0.0018 and 0.0012, respectively). Further, a haplotype analysis of these 2 SNPs suggested that the haplotypes containing either of the minor alleles were protective against alcohol withdrawal relative to the ancestral haplotype (p = 0.000006).

CONCLUSIONS

These results suggest that variants in the ADH1B and ADH4 genes may be protective against the development of some symptoms associated with alcohol dependence.

Alcohol and aldehyde dehydrogenase polymorphisms in Chinese and Indian populations

The association between two functional polymorphisms in alcohol dehydrogenase (ADH2/ADH1B) and aldehyde dehydrogenase (ALDH2) genes and alcohol dependence was examined in 182 Chinese and Indian patients undergoing treatment for alcohol dependence and 184 screened control subjects from Singapore. All subjects were screened by the Alcohol Use Disorders Identification Test (AUDIT). Patients were also administered the Severity of Alcohol Dependence Questionnaire (SADQ). Polymorphisms were genotyped by allele-specific polymerase chain reaction and selected genotypes confirmed by DNA sequencing or restriction fragment length polymorphism. Our results showed that frequencies of ADH1B*2 and ALDH2*2 were higher in controls compared to alcohol-dependent subjects for both Chinese and Indians. Frequencies of these two alleles were also higher in the 104 Chinese controls compared to the 80 Indian controls. None of the eight Chinese who were homozygous for both protective alleles was alcohol dependent. The higher frequencies of the protective alleles could explain the lower rate of alcohol dependence in Chinese.

Ethnic Origin of Alcoholics Admitted to an Israeli Treatment Center

Jews have a low rate of alcohol use and abuse as reported in several different countries. In Israel over the last 10 years there has been a rising rate of alcoholism. We studied consecutive new admissions to our inpatient alcohol center, and an age and sex matched comparison group of patients consecutively admitted with schizophrenia for whether each of their four grandparents was Jewish, or non-Jewish. A significantly higher percentage of alcohol-related admissions were immigrants from the Former Soviet Union (FSU) than among schizophrenics. Among the alcohol-related admissions from the FSU, there were significantly fewer Jewish grandparents than among schizophrenia patients from the FSU. These data could support the concept that biological Jewish ethnicity has a protective effect against alcohol abuse, but are also consistent with cultural transmission of Jewish attitudes toward alcohol use.

Specific phobia in older adults: evidence from the national epidemiologic survey on alcohol and related conditions

OBJECTIVE

This study aims to investigate: 1) the association of specific phobia with childhood parental loss and recent stressful life events; 2) the coexistence of specific phobia and major depressive disorders (MDDs); and 3) the impact of specific phobia on medical conditions, obesity, health service utilization, and health-related quality of life.

DESIGN

Cross-sectional observational study.

SETTING

The National Epidemiologic Survey on Alcohol and Related Conditions (2001-2002), a national representative survey of the noninstitutionized U.S. household population.

PARTICIPANTS

The 8,205 respondents aged 65 and above.

MEASUREMENTS

Specific phobia was assessed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule-Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition version. Demographic characteristics, psychosocial risk factors, psychiatric disorders, health-related quality of life, obesity, medical conditions, and health service utilization were measured.

RESULTS

The current and lifetime prevalence of specific phobia were 4.51% and 6.05%, respectively. Multivariate analyses revealed that specific phobia was more common among younger age groups, women, and those who reported stressful life events but less common among foreign-born individuals. In addition, MDD was significantly related to lifetime specific phobia. Specific phobia was also significantly related to a lower health-related quality of life and two medical conditions.

CONCLUSION

Our prevalence rates of specific phobia in the elderly are at the lower end of the ranges identified in the previous studies. The correlation between specific phobia and MDD raises further questions about the nature of specific phobia in the elderly. This study supports the notion that specific phobia has a strong impact on the quality of life in old age.

Associations of ALDH2 and ADH1B genotypes with alcohol-related phenotypes in Asian young adults

BACKGROUND

Associations of ALDH2 and ADH1B genotypes with alcohol use have been evaluated largely using case-control studies, which typically focus on adult samples and dichotomous diagnostic outcomes. Relatively fewer studies have evaluated ALDH2 and ADH1B in relation to continuous drinking outcomes or at different developmental stages. This study examined additive and interactive effects of ALDH2 and ADH1B genotypes on drinking behavior in a mixed-gender sample of Asian young adults, focusing on continuous phenotypes (e.g., heavy episodic and hazardous drinking, alcohol sensitivity, drinking consequences) whose expression is expected to precede the onset of alcohol use disorders.

METHODS

The sample included 182 Chinese- and Korean-American young adults ages 18 years and older (mean age = 20 years). Effects of ALDH2, ADH1B and ethnicity were estimated using generalized linear modeling.

RESULTS

The ALDH2*2 allele predicted lower reported rates of alcohol use and drinking consequences as well as greater reported sensitivity to alcohol. There were significant ethnic group differences in drinking outcomes, such that Korean ethnicity predicted higher drinking rates and lower alcohol sensitivity. ADH1B status was not significantly related to drinking outcomes.

CONCLUSIONS

Ethnicity and ALDH2 status, but not ADH1B status, consistently explained significant variance in alcohol consumption in this relatively young sample. Results extend previous work by showing an association of ALDH2 genotype with drinking consequences. Findings are discussed in the context of possible developmental and population differences in the influence of ALDH2 and ADH1B variations on alcohol-related phenotypes.

Influence of a drinking quantity and frequency measure on the prevalence and demographic correlates of DSM-IV alcohol dependence

BACKGROUND

Recent research suggests that adding a quantity/frequency alcohol consumption measure to diagnoses of alcohol use disorders may improve construct validity of the diagnoses for Diagnostic and Statistical Manual of Mental and Behavior Disorders (DSM-V). This study explores the epidemiological impact of including weekly at-risk drinking (WAD) in the DMS-IV diagnostic definition of alcohol dependence via 3 hypothetical reformulations of the current criteria.

METHODS

The sample was the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative sample with 43,093 adults aged >18 in the U.S interviewed with the Alcohol Use Disorder and Associated Disabilities Interview Schedule IV. The current (DSM-IV) definition of alcohol dependence was compared with 4 hypothetical alcohol dependence reformulations that included WAD: (1) WAD added as an eighth criteria; (2) WAD required for a diagnosis; (3) adding abuse and dependence criteria together, and including WAD with a 3 of 12 symptom threshold; (4) adding abuse and dependence criteria together, and including WAD with a 5 of 12 symptom threshold.

RESULTS

The inclusion of at-risk drinking as an eighth criterion of alcohol dependence has a minimal impact on the sociodemographic correlates of alcohol dependence but substantially increases the prevalence of dependence (from 3.8% to 5.0%). At-risk drinking as a required criterion or as part of a diagnosis that combines abuse with dependence criteria with a higher threshold (5+ criteria) decreases prevalence and has a larger impact on sociodemographic correlates. Blacks, Hispanics, and women are less likely to be included in diagnostic reformulations that include WAD, whereas individuals with low-income and education are more likely to remain diagnosed.

CONCLUSIONS

Including WAD as either a requirement of diagnosis or as an additional criterion would have a large impact on the prevalence of alcohol dependence in the general population. The inclusion of a quantity/frequency requirement may eliminate false positives from studies of alcohol disorder etiology and improve phenotype definition for genetic association studies by reducing heterogeneity in the diagnosis, but may also reduce eligibility for treatment services among women and racial/ethnic minorities compared.

Mental health implications of migration: a review of mental health community studies on Russian-speaking immigrants in Israel

INTRODUCTION

Since late 1980s, 1,001,726 immigrants arrived in Israel from the former Soviet Union (FSU). A review of community studies on the mental health of these immigrants is presented.

METHOD

Israeli studies from the past two decades were reviewed. Presented are findings on the prevalence of psychological distress and psychiatric disorders as well as on a number of risk factors among FSU immigrants.

RESULTS

Higher psychological distress and psychiatric morbidity were consistently found among FSU immigrants compared to the Israel-born. Social support was identified as a major stress-mitigating factor in migration. Most studies reveal the persistence of psychological distress among FSU immigrants during the first 5 years following migration, with a risk period around the second and third years following migration.

DISCUSSION

Findings from Israel corroborate some findings on immigrants in other countries but as they are limited to a single immigrant population, replication of these studies is necessary.

A biosocial explanation of delinquency abstention

BACKGROUND

One of the more influential criminological theories advanced in recent years is Moffitt's developmental taxonomy. A line of research has tested the core propositions from her theory regarding the causes of life-course persistent offenders and the causes of adolescence-limited offenders, but very little research has investigated whether Moffitt's explanation of delinquency abstention is supported empirically.

AIM

To examine the biosocial correlates of delinquency abstention.

METHOD

We used data from the National Longitudinal Study of Adolescent Health (Add Health) to examine the effects of two dopamine receptor genes (the dopamine D2 receptor gene (DRD2) and the dopamine D4 receptor gene (DRD4)), drug-using peers, neighbourhood problems, low self-control, public assistance, age, race, and gender on delinquency abstention. The statistical models were calculated by employing binary logistic regression.

RESULTS

Analysis of the Add Health data revealed that exposure to drug-using peers and levels of self-control were associated with abstention from delinquency. In addition, there was some evidence suggesting that DRD2 and DRD4 had protective effects against delinquent involvement for males.

CONCLUSION

A multifactorial arrangement of environmental and genetic factors contributes to delinquency abstention.

Pharmacokinetic and pharmacodynamic basis for partial protection against alcoholism in Asians, heterozygous for the variant ALDH2*2 gene allele

OBJECTIVES

It has been well documented that although homozygosity of the variant aldehyde dehydrogenase-2 (ALDH2) gene allele, ALDH2*2, in Asians almost fully protects against alcoholism, the heterozygosity only affords a partial protection to varying degrees. The full protection against alcoholism has been ascribed to the low-amount of alcohol hypersensitivity accompanied by a prolonged and large accumulation of acetaldehyde in blood (Peng et al. Pharmacogenetics 1999; 9:463-476). The physiological basis for the partial protection, however, remains unclear.

METHODS

To address this question, we recruited a total of 32 adult Han Chinese men, matched by age, body-mass index, and nutritional state from a population base of 404 men. The subjects were divided into 3 combinatorial genotypic groups of alcohol dehydrogenase (ADH) and ALDH, that is, ALDH2*1/*1-ADH1B*1/*1-ADH1C*1/*1 (n=8), ALDH2*1/*1-ADH1B*2/*2-ADH1C*1/*1 (n=8), and ALDH2*1/*2-ADH1B*2/*2-ADH1C*1/*1 (n=16). Following a moderate dose of ethanol (0.5 g/kg body weight), blood ethanol/acetaldehyde/acetate concentrations, cardiac and extracranial/intracranial arterial hemodynamic parameters, as well as self-rated subjective sensations, were measured for 130 min.

RESULTS

Heterozygotic ALDH2*1/*2 subjects were found to be strikingly responsive to the moderate amount of alcohol, as evidenced by the prominent cardiovascular effects as well as subjective perceptions of general discomfort for as long as 2 h following ingestion. The ADH1B polymorphisms did not appear to correlate with the pharmacokinetic and pharmacodynamic effects.

CONCLUSIONS

These results indicate that acetaldehyde, rather than ethanol or acetate, is primarily responsible for the observed alcohol sensitivity reactions and suggest that substantially lower accumulation of blood acetaldehyde in the heterozygotes significantly reduces the aversion reaction to low amounts of alcohol that permits other biological as well as environmental factors to facilitate drinking and the according risk for the disease.

Effect of ADH1B genotype on alcohol consumption in young Israeli Jews

BACKGROUND

The alcohol dehydrogenase 1B (ADH1B) genotype affects the risk for alcoholism, with elevated prevalence of a protective allele in Jews. Alcohol consumption is increasing among younger Israeli Jews, reflecting environmental influences. We investigated whether the relationship of ADH1B genotype with alcohol consumption differed between younger and older adult Israelis.

METHODS

Israeli community residents aged 22 to 65 participated in a structured interview that included questions on the maximum number of drinks on an occasion (Maxdrinks). The ADH1B genotype was determined for 68 participants and dichotomized into nonprotective (ADH1B(*)1/1) and protective (ADH1B(*)1/2 or ADH1B(*)2/2) genotypes. Using Maxdrinks as the dependent variable, Poisson's regression was used to test an age x genotype interaction.

RESULTS

The ADH1B genotype interacted significantly with age (p=0.01) in a Poisson's model with Maxdrinks as the outcome. Among participants >or=33 years, Maxdrinks was low and unrelated to the ADH1B genotype. Among participants <33 years with ADH1B(*)1/2 or ADH1B(*)2/2, Maxdrinks was also low (mean, 2.6 drinks) but among those with ADH1B(*)1/1, Maxdrinks was substantially higher (mean, 6.2 drinks).

CONCLUSION

Maximum lifetime drinking among younger adult Israelis without genetic protection exceeded thresholds for risky and unsafe drinking (>or=5 drinks). Environmental influences promoting greater drinking among younger Israelis may particularly affect those with the nonprotective, more common ADH1B genotype.

A rational approach to the pharmacotherapy of alcohol dependence

The use of alcohol is widespread in the world, and although there are many regular users, some individuals drink excessively. Understanding the time course of the development and maintenance of alcohol dependence is important in assessing the potential risk/benefit of an intervention and in accurately treating the problem. Most, although not all, literature suggests that alcoholism is a chronic, relapsing disorder and that there is a general progression from less to more severe problems. Understanding the neurobiology that underlies alcohol dependence as it relates to different clinical stages may help in the development of effective targeted pharmacological treatments. Important clinical stages that may be amenable to pharmacological intervention include the transition from alcohol use to heavy drinking particularly in vulnerable individuals, the cessation of heavy drinking in individuals who want to quit, and the prevention of relapse in individuals who have initiated abstinence but may struggle with craving or the desire to resume alcohol use. Neurotransmitter systems implicated in these stages include glutamate, gamma-aminobutyric acid, opioid, and serotonin systems that may act directly or via the indirect modulation of dopamine function. The treatment implications will also be discussed.

Associations of variations in alcohol dehydrogenase genes with the level of response to alcohol in non-Asians

BACKGROUND

Risk and protective factors for alcohol use disorders (AUDs) are complex and reflect both environmental and genetic factors. Genetic components account for about 50% of the variation and influence several phenotypes, including the level of response (LR) to alcohol as well as alcohol-metabolizing enzyme polymorphisms. Variations in the ADH1B and ADH1C genes may influence the LR to alcohol by increasing levels of acetaldehyde during alcohol metabolism, although most data on this question come from Asian populations.

METHODS

This study evaluated associations of ADH1B and ADH1C genotypes in a non-Asian sample. Participants (N = 117, 69.2% female) were 18- to 29-year-old men and women, primarily Caucasian (70.1%) and black (26.5%), recruited in San Diego, California. The Semi-Structured Assessment for the Genetics of Alcoholism Interview was used to assess demographic, substance use, and psychiatric history information, and the Family History Assessment Module was used to determine first-degree family history of alcohol dependence. An alcohol challenge paradigm was used to gather data on the LR to alcohol over 210 minutes.

RESULTS

Participants with the ADH1B*1/*2 genotype had a higher LR to alcohol early in the alcohol challenge (i.e., 30, 60, and 90 minutes after drinking) as measured by both alcohol-related changes in subjective feelings of intoxication and body sway, even when controlling for sex and Russian/Eastern European ancestry. A similar trend was seen for ADH1C*1/*1 genotype, although the results were not significant.

CONCLUSIONS

These findings suggest that studies searching for genes relating to the LR to alcohol as a vulnerability factor for AUDs should consider controlling for ADH1B genotype, as the ADH1B*2 allele could obscure the impact of other genetic polymorphisms.

The genetics of alcoholism: identifying specific genes through family studies

Alcoholism is a complex disorder with both genetic and environmental risk factors. Studies in humans have begun to elucidate the genetic underpinnings of the risk for alcoholism. Here we briefly review strategies for identifying individual genes in which variations affect the risk for alcoholism and related phenotypes, in the context of one large study that has successfully identified such genes. The Collaborative Study on the Genetics of Alcoholism (COGA) is a family-based study that has collected detailed phenotypic data on individuals in families with multiple alcoholic members. A genome-wide linkage approach led to the identification of chromosomal regions containing genes that influenced alcoholism risk and related phenotypes. Subsequently, single nucleotide polymorphisms (SNPs) were genotyped in positional candidate genes located within the linked chromosomal regions, and analyzed for association with these phenotypes. Using this sequential approach, COGA has detected association with GABRA2, CHRM2 and ADH4; these associations have all been replicated by other researchers. COGA has detected association to additional genes including GABRG3, TAS2R16, SNCA, OPRK1 and PDYN, results that are awaiting confirmation. These successes demonstrate that genes contributing to the risk for alcoholism can be reliably identified using human subjects.

Substance use disorders: Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) and International Classification of Diseases, tenth edition (ICD-10)

AIMS

Two major nomenclatures, Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) and International Classification of Diseases, tenth edition (ICD-10), currently define substance use disorders for broad audiences of users with different training, experience and interests. A comparison of these definitions and their implications for DSM-V and ICD-11 has not been available.

METHODS

The background for the dependence concept and abuse, harmful use, withdrawal, substance-induced disorders and remission and other substance-related conditions is reviewed. Reliability evidence is presented, as is validity evidence from approaches including psychometric, genetic and animal studies. The relevance of the DSM-IV and ICD-10 compared to alternative systems (e.g. the Addiction Severity Index) is considered.

RESULTS

Reliability and psychometric validity evidence for substance dependence is consistently strong, but more mixed for abuse and harmful use. Findings on the genetics of alcohol disorders support the validity of the dependence concept, while animal studies underscore the centrality of continued use despite negative consequences to the concept of dependence. While few studies on substance-induced disorders have been conducted, those published show good reliability and validity when elements of DSM-IV and ICD-10 are combined.

CONCLUSIONS

Dependence in DSM-V and ICD-11 should be retained, standardizing both criteria sets and adding a severity measure. The consequences of heavy use should be measured independently of dependence; add cannabis withdrawal if further research supports existing evidence; conduct further studies of the substance-induced psychiatric categories; standardize their criteria across DSM-V and ICD-11; develop a theoretical basis for better remission criteria; consider changing substance 'abuse' to substance 'dysfunction disorder'; and conduct clinician education on the value of the diagnostic criteria.

Genetic associations of alcohol and aldehyde dehydrogenase with alcohol dependence and their mechanisms of action

Two alcohol dehydrogenase genes (ADHIB and ADH1C on chromosome 4) and one aldehyde dehydrogenase gene (ALDH2 on chromosome 12) exhibit functional polymorphisms that are associated with lower rates of alcohol dependence. The ALDH2*2 allele,found almost exclusively in Asian populations, has the strongest relationship. The ADH1B*2, ADH1B*3, and ADHlC*i alleles, found in varying prevalence in different ethnic groups, have also been associated with lower rates of alcohol dependence. Studies of the ADHIBand ADH1C haplotypes, however, have shown that ADH1C*I is in linkage disequilibrium with ADHiB*2, and the ADH1C*i allele does not appear to have significant unique associations with alcohol dependence. The hypothesized mechanism underlying the associations of the ADH1B and ALDH2 polymorphisms with alcohol dependence is that the isoenzymes encoded by these alleles lead to an accumulation of acetaldehyde during alcohol metabolism. Based on their kinetic properties, ALDH2 *2 theoretically should lead to a slower removal of acetaldehyde than ALDH2*1, whereas ADH1B*2 and ADH1B*3 should lead to a more rapid production of acetaldehyde than ADHIB*I. It is further hypothesized that elevations in acetaldehyde cause more intense reactions to alcohol and lead to lower levels of alcohol intake. Data are consistent with the hypothesis that elevations in acetaldehyde, increased sensitivity to alcohol, and lower levels of drinking reflect the mechanism by which the ALDH2*2 allele reduces risk for alcohol dependence. There is also some evidence supporting this mechanism for the ADH1B*2 and ADHIB*3 alleles, but the results are less consistent. These findings highlight the value of trying to elucidate the mechanism by which genes ultimately give rise to differences in alcohol dependence through the examination of mediating behaviors.

The alcohol clamp: applications, challenges, and new directions--an RSA 2004 symposium summary

This article summarizes the proceedings of a symposium organized and cochaired by Vijay Ramchandani and Sean O'Connor and presented at the 2004 Research Society on Alcoholism meeting in Vancouver, BC, Canada. The objectives of this symposium were: (1) to provide a rationale for the development and use of the alcohol clamp and the requirements for its use in alcohol challenge studies; (2) to highlight recent studies conducted using the alcohol clamp to identify sources of variation in the pharmacokinetics and pharmacodynamics of alcohol, as well as to address important research questions related to the relationship between the response to alcohol and the risk for alcoholism; and (3) to provide a perspective on progress, address limitations of the clamp, and identify new directions for alcohol challenge research. The symposium began with an introduction and overview of the alcohol clamp, by Vijay Ramchandani. This was followed by 4 presentations that highlighted recent studies conducted using the clamp including: (1) determination of the influence of alcohol dehydrogenase polymorphisms on alcohol elimination rates in a male Jewish population, by Yehuda Neumark; (2) examination of family history of alcoholism, recent drinking history, and levels and rates of administration as determinants of the response to alcohol and risk for alcoholism, by Sean O'Connor; (3) evaluation of the time course of ethanol intoxication on neuroendocrine function in humans, by Ulrich Zimmermann; and (4) a study of the effects of steady-state blood alcohol levels on auditory event-related potentials in rats, by Sandra Morzorati. Harriet de Wit summarized and discussed the research presented at the symposium and provided her perspective on future directions for research using the alcohol clamp.

Genetic associations of alcohol dehydrogenase with alcohol use disorders and endophenotypes in white college students

Associations of alcohol dehydrogenase (ADH) gene polymorphisms (ADH1B*2 and ADH1C*1) with a lifetime alcohol use disorder (AUD) were examined in White college students. Alcohol-related endophenotypes likely to be influenced by elevations in acetaldehyde were also assessed. Individuals with an ADH1B*2 allele had lower rates of AUDs, consumed a lower maximum number of drinks in a 24-hr period, reported a greater level of response to alcohol, were more likely to have experienced alcohol-induced headaches following 1 or 2 drinks, and reported more severe hangovers than those lacking this allele. These findings are consistent with the hypothesis that enhanced sensitivity to alcohol and lower levels of alcohol use reflect the mechanism by which ADH1B*2 protects against developing an AUD.

Polymorphisms in the mitochondrial aldehyde dehydrogenase gene (Aldh2) determine peak blood acetaldehyde levels and voluntary ethanol consumption in rats

Dependence on alcohol, a most widely used drug, has a heritability of 50-60%. Wistar-derived rats selectively bred as low-alcohol consumers for many generations present an allele (Aldh2(2)) of mitochondrial aldehyde dehydrogenase that does not exist in high-alcohol consumers, which mostly carry the Aldh2(1) allele. The enzyme coded by Aldh2(2) has a four- to five-fold lower affinity for NAD than that coded by Aldh2(1). The present study was designed to determine whether these polymorphisms account for differences in voluntary ethanol intake and to investigate the biological mechanisms involved. Low-drinker F0 Aldh2(2)/Aldh2(2) rats were crossed with high-drinker F0 Aldh2(1)/Aldh2(1) rats to obtain an F1 generation, which was intercrossed to obtain an F2 generation that segregates the Aldh2 alleles from other genes that may have been coselected in the breeding for each phenotype. Data show that, with a mixed genetic background, F2 Aldh2(1)/Aldh2(1) rats voluntarily consume 65% more alcohol (P<0.01) than F2 Aldh2(2)/Aldh2(2) rats. A major phenotypic difference was a five-fold higher (P<0.0025) peak blood acetaldehyde level following ethanol administration in the lower drinker F2 Aldh2(2)/Aldh2(2) compared to the higher drinker F2 Aldh2(1)/Aldh2(1) animals, despite the existence of identical steady-state levels of blood acetaldehyde in animals of both genotypes. Polymorphisms in Aldh2 play an important role in: (i) determining peak blood acetaldehyde levels and (ii) modulating voluntary ethanol consumption. We postulate that the markedly higher peak of blood acetaldehyde generated in Aldh2(2)/Aldh2(2)(2) animals is aversive, leading to a reduced alcohol intake in Aldh2(2)/Aldh2(2) versus that in Aldh2(1)/Aldh2(1) animals.

The level of response to alcohol in daughters of alcoholics and controls

BACKGROUND

The low level of response (LR) to alcohol is a genetically influenced characteristic related to the development of alcohol use disorders (AUDs). This phenotype is found in men with a family history (FH) of alcoholism, predicts future AUDs, and has heritabilities as high as 60%. However, despite evidence of genetic influences for AUDs in both sexes, the majority of studies evaluating differences in LR across high- and low-risk groups have been conducted on males, and it is unclear how generalizable these results are to women.

METHODS

Twenty-five women who are family history positive (FHP) for alcohol dependence were matched with 25 women with no FH of alcoholism (FHN) on factors that may impact LR. Using an alcohol challenge paradigm, data on the reaction to a moderate dose of alcohol were gathered over a period of 3.5 h. Assessments included breath alcohol concentrations (BrACs), the Subjective High Assessment Scale (SHAS), as well as body sway or static ataxia.

RESULTS

Family history positives reported lower subjective intoxication than FHNs. In addition, when body sway scores were corrected for skewness, FHPs had significantly lower scores on alcohol-related changes in lateral sway. These differences remained after considering the effects of drinking history and BrAC values.

CONCLUSIONS

This study evaluated the LR to alcohol in the largest sample of alcohol challenges in matched FHP and FHN women to date. Overall, the findings are consistent with most data from earlier investigations of smaller sized samples of FHP women. The results suggest that, similar to sons of alcoholics, a low LR to alcohol might also be characteristic of daughters of alcoholics.

Functionality of allelic variations in human alcohol dehydrogenase gene family: assessment of a functional window for protection against alcoholism

Alcohol dehydrogenase (ADH) catalyses the rate-determining reaction in ethanol metabolism. Genetic association studies of diverse ethnic groups have firmly demonstrated that the allelic variant ADH1B*2 significantly protects against alcoholism but that ADH1C*1, which is in linkage with ADH1B*2, produces a negligible protection. The influence of other potential candidate genes/alleles within the human ADH family, ADH1B*3 and ADH2, remains unclear or controversial. To address this question, functionalities of ADH1B3 and ADH2 were assessed at a physiological level of coenzyme and substrate range. Ethanol-oxidizing activities of recombinant ADH1B1, ADH1B2, ADH1B3, ADH1C1, ADH1C2 and ADH2 were determined at pH 7.5 in the presence of 0.5 mm NAD with 2-50 mm ethanol. The activity differences between ADH1B2 and ADH1B1 were taken as a threshold for effective protection against alcoholism and those between ADH1C1 and ADH1C2 as a threshold for null protection. Over 2-50 mm ethanol, the activities of ADH1B3 were found 2.9-23-fold lower than those of ADH1B2, largely attributed to the Km effect (ADH1B2, 1.8 mm; ADH1B3, 61 mm). Strikingly, the ADH1B3 activity was only 84% that of ADH1B1 at a low ethanol concentration, 2 mm, but increased 10-fold at 50 mm. Corrected for relative expression levels of the enzyme in liver, the hepatic ADH2 activities were estimated to be 18-97% those of ADH1B1 over 2-50 mm ethanol and were 28-140% of the activity differences between ADH1C1 and ADH1C2. The assessment based on the proposed functional window for the human ADH gene family indicates that ADH1B*3 may show some degree of protection against alcoholism and that the ADH2 functional variants appear to be negligible for this protection.

Allelic and haplotypic association of GABRA2 with alcohol dependence

Alcohol dependence is a highly prevalent disorder that is associated with serious morbidity and mortality. Because the GABAA neurotransmitter receptor is an important mediator for several behavioral effects of alcohol, genes encoding GABA-related proteins are functional candidates to influence risk of alcohol dependence. Two genome-wide scans showed linkage of alcohol dependence to a region on chromosome 4p, which contains a cluster of genes encoding GABAA receptor subunits. A recent effort to fine map that region showed a haplotypic association of alcohol dependence to the gene encoding the GABAA receptor alpha-2 subunit (GABRA2). We examined 10 single nucleotide polymorphisms (SNPs) spanning the coding region of this gene in samples of European American subjects with alcohol dependence (n = 446), and controls (n = 334) screened to exclude substance use disorders. There was evidence of association to alcohol dependence for seven adjacent markers spanning 98,000 bp in the middle and 3'-portion of the GABRA2 gene (range of P-values = 0.008-0.03). When the subset of the alcohol-dependent subjects excluding those with a diagnosis of cocaine or opioid dependence or major depressive episode (n = 198) was examined, the strength of the association was increased across these 7 SNPs (range of P-values = 0.002-0.007). Two common haplotypes in this region accounted for 90.8% of chromosomes. The more common haplotype was present in 55.6% of control group chromosomes versus 48.2% of alcohol-dependent subjects (P = 0.007) and 45.8% of subjects with alcohol dependence but no co-morbid drug dependence or depression (P = 0.003). These findings replicate and extend recently reported findings, which together underscore the potential contribution of polymorphic variation at the GABRA2 locus to the risk for alcohol dependence.

Alcohol Dehydrogenase Polymorphisms Influence Alcohol-Elimination Rates in a Male Jewish Population

BACKGROUND

Genetic variation in the alcohol dehydrogenase (ADH) enzyme is associated with an aversion to alcohol and a lower risk of alcoholism among Asians. There is growing evidence of a functional role of the ADH2*2 allele in alcohol-drinking patterns among Jews, who have traditionally exhibited low rates of alcoholism and alcohol-related problems. The mechanism by which this allelic effect is mediated is not yet clearly understood. This study examined the effect of ADH2*2 on alcohol-elimination rates (AER) under experimental conditions.

METHODS

Young adult male Jews (N = 109) received an intravenous alcohol infusion; metabolism was measured by using standard breath alcohol concentration tests. A clamping technique was used to achieve and maintain a target breath alcohol concentration of 50 mg/100 ml for a defined time period. The AER at steady state was calculated. The alcohol disappearance rate was also calculated from the descending limb slope. Polymerase chain reaction was used for allelic determination of the ADH2 and ADH3 loci.

RESULTS

The mean AER among ADH2*2 carriers was significantly higher (8.09 +/- 1.4 g/hr) than among ADH2*1 homozygotes (7.14 +/- 1.5 g/hr; p = 0.003). Significance was retained on adjustment for potential confounding covariates. The ADH2 allele explains 8.5% of the AER variance in this population. Little AER difference was observed across ADH3 genotype groups. The slope of the descending limb increased with increasing copies of the ADH2*2 allele.

CONCLUSIONS

The rate of alcohol elimination is significantly associated with the ADH2 genotype of Jewish males. Evidence for variation in alcohol metabolism across ADH genotypic groups provides support for the role of physiologic protective factors in alcohol drinking and suggests that reduced drinking among Jews may be genetically as well as environmentally determined. We believe that application of the novel "Indiana clamp" enhances AER measurement accuracy, allowing for detection of hitherto undetectable differences.