Read the Article by Edwards and Mackay (2009), "Quantitative Trait

Essay

Read the article by Edwards and Mackay (2009), "Quantitative Trait Loci for Aggressive Behavior in Drosophila melanogaster" (Genetics, vol. 182, pp. 889-897). How did the authors evaluate aggression in these flies? Can you think of any alternative methods for quantifying aggression in a more standardized fashion? Next, describe the authors' approach to identifying QTLs associated with aggressive behavior. They found that many of the QTLs interact epistatically. What is epistasis and how do epistatic interactions introduce significant challenges to understanding the genetic basis of complex behaviors like aggression? (See also Zwarts et al. 2011 and Anholt & Mackay 2012.)