The Genetic Complexity of Alcohol Drinking in Rodents

This chapter first discusses the alcohol-drinking phenotypes most commonly used in rodent genetic studies. The emphasis is on the complexity of the phenotypic spaces encompassed by the drinking assays (many of which are amalgamations of multiple approaches). It then reviews the evidence for genetic contributions to those drinking traits. For several of them, there is unequivocal evidence for genetic contributions to individual differences in drinking, and for one of them, two-bottle preference drinking, there are voluminous data. Finally, it discusses the genetic singularity of each trait versus what appear to be pleiotropic genetic influences (those in which one or more genes influence multiple traits related to drinking). Sorting out this genetic complexity is difficult because genetic information is sparse for many drinking-related behaviors, and many procedures are used in combination with others.