School of Medicine Publications and Presentations
Shared genetic factors influence amygdala volumes and risk for alcoholism
Document Type
Article
Publication Date
1-1-2015
Abstract
Alcohol abuse and dependence (alcohol use disorders, AUDs) are associated with brain shrinkage. Subcortical structures including the amygdala, hippocampus, ventral striatum, dorsal striatum, and thalamus subserve reward functioning and may be particularly vulnerable to alcohol-related damage. These structures may also show pre-existing deficits impacting the development and maintenance of AUD. It remains unclear whether there are common genetic features underlying both subcortical volumes and AUD. In this study, structural brain images were acquired from 872 Mexican-American individuals from extended pedigrees. Subcortical volumes were obtained using FreeSurfer, and quantitative genetic analyses were performed in SOLAR. We hypothesized the following: (1) reduced subcortical volumes in individuals with lifetime AUD relative to unrelated controls; (2) reduced subcortical volumes in individuals with current relative to past AUD; (3) in non-AUD individuals, reduced subcortical volumes in those with a family history of AUD compared to those without; and (4) evidence for common genetic underpinnings (pleiotropy) between AUD risk and subcortical volumes. Results showed that individuals with lifetime AUD showed larger ventricular and smaller amygdala volumes compared to non-AUD individuals. For the amygdala, there were no differences in volume between current vs past AUD, and non-AUD individuals with a family history of AUD demonstrated reductions compared to those with no such family history. Finally, amygdala volume was genetically correlated with the risk for AUD. Together, these results suggest that reduced amygdala volume reflects a pre-existing difference rather than alcohol-induced neurotoxic damage. Our genetic correlation analysis provides evidence for a common genetic factor underlying both reduced amygdala volumes and AUD risk.
Recommended Citation
Dager, A. D., McKay, D. R., Kent, J. W., Jr, Curran, J. E., Knowles, E., Sprooten, E., Göring, H. H., Dyer, T. D., Pearlson, G. D., Olvera, R. L., Fox, P. T., Lovallo, W. R., Duggirala, R., Almasy, L., Blangero, J., & Glahn, D. C. (2015). Shared genetic factors influence amygdala volumes and risk for alcoholism. Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 40(2), 412–420. https://doi.org/10.1038/npp.2014.187
First Page
412
Last Page
420
Publication Title
Neuropsychopharmacology
DOI
10.1038/npp.2014.187
Academic Level
faculty
Mentor/PI Department
Office of Human Genetics
Comments
Copyright © 2015 American College of Neuropsychopharmacology