A brief history of research on the genetics of alcohol and other drug use disorders.

ObjectiveThis article reviews developments in research on genetic influences on alcohol and other drug use and disorders over the past 7 decades.MethodThe author began with a review of the flow and content of articles published in the three iterations of the journal since 1940 and then used a PubMed search of genetics of alcohol and other drug-related topics to gain a broad overview of developments in this field.ResultsThe literature demonstrates the rapid metamorphosis of genetic research from the ideas of Mendel to an understanding that the substance use disorders are complex, genetically influenced conditions where genes explain up to 60% of the picture. Most genes operate through additional intermediate characteristics, such as impulsivity and a low sensitivity to alcohol, some of which are substance specific and others related to substances in general. Using linkage, association, genome-wide association, and other modern methods, investigators have identified a diverse range of genetic variations that affect substance-related phenomena.ConclusionsGenetic studies regarding alcohol and other drug use and problems have grown dramatically in the past 75 years. We currently have a much more sophisticated understanding of these influences, and the rapid development of new methods has the promise of continuing what has been a solid contribution of important findings in recent years

Alcohol, Anxiety, and Depressive Disorders.

Alcoholics frequently experience episodes of intense depression and/or severe anxiety. Depressed or anxious alcohol-dependent people often believe that they drink to relieve symptoms of sadness or nervousness. However, research does not unanimously support the prior existence of severe depressive or anxiety disorders as a usual cause of alcoholism. A review of recent literature (from family studies, prospective investigations, and studies of children of alcoholics) on the complex interaction between alcohol dependence and independent anxiety/depressive disorders reveals that if an association between alcoholism and anxiety/depressive disorders does exist, it likely operates in a relatively small subgroup of alcoholics at the same time. Psychological symptoms may carry a worse prognosis for alcohol-related problems, and these symptoms must be addressed early in alcoholism treatment

Predictors of Increases in Alcohol Problems and Alcohol Use Disorders in Offspring in the San Diego Prospective Study.

BackgroundThe 35-year-long San Diego Prospective Study documented 2-fold increases in alcohol problems and alcohol use disorders (AUDs) in young-adult drinking offspring compared to rates in their fathers, the original probands. The current analyses use the same interviews and questionnaires at about the same age in members of the 2 generations to explore multiple potential contributors to the generational differences in adverse alcohol outcomes.MethodsUsing data from recent offspring interviews, multiple cross-generation differences in characteristics potentially related to alcohol problems were evaluated in 3 steps: first through direct comparisons across probands and offspring at about age 30; second by backward linear regression analyses of predictors of alcohol problems within each generation; and finally third through R-based bootstrapped linear regressions of differences in alcohol problems in randomly matched probands and offspring.ResultsThe analyses across the analytical approaches revealed 3 consistent predictors of higher alcohol problems in the second generation. These included the following: (i) a more robust relationship to alcohol problems for offspring with a low level of response to alcohol; (ii) higher offspring values for alcohol expectancies; and (iii) higher offspring impulsivity.ConclusionsThe availability of data across generations offered a unique perspective for studying characteristics that may have contributed to a general finding in the literature of substantial increases in alcohol problems and AUDs in recent generations. If replicated, these results could suggest approaches to be used by parents, healthcare workers, insurance companies, and industry in their efforts to mitigate the increasing rates of alcohol problems in younger generations