Defense Date


Document Type


Degree Name

Doctor of Philosophy


Human Genetics

First Advisor

Danielle Dick


Decades of work has led researchers to believe that risk for complex behavioral phenotypes, such as alcohol use disorders, is likely influenced by multiple genes of small effect acting in conjunction with each other and the environment. Currently, the field of psychiatric genetics is developing methodologies for the identification of genetic risk variants that predispose individuals to the development of complex behavioral disorders. Several challenges related to the complex and polygenic nature of these phenotypes, must be considered. This dissertation study attempts to address these important challenges in the context of alcohol use disorders and related phenotypes. A rich twin and family study literature has indicated that 40-70% of the variance in alcohol use disorders (AUDs) is influenced by genetics. Recent attempts to identify specific x genetic risk variants associated with AUDs have been met with limited success. Meanwhile, evidence of the moderating effects of the environment on AUDs has been mounting, providing a strong rationale for examining gene-environment interaction. In the following chapters several studies will be described that integrate established twin methodologies into gene identification projects in an effort to reduce heterogeneity (both phenotypic and genotypic), elucidate environmental constructs that moderate genetic influences, and to enhance statistical power to detect the subtle genetic influences on alcohol related phenotypes.


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Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

July 2012