Linkage studies versus quantitative genetics

Professor Allen Moore outlines the differences between quantitative genetics and linkage studies. With quantitative genetics it is not necessary to begin with the physical DNA.

So linkage studies and quantitative genetics both rely on statistical associations, but linkage is actually taking a physical piece of the genome and showing that that physical piece is associated with differences in a given phenotype. So if you have differences in the sequence, so you have sequenced everything again, and you find that those differences correspond to differences in a trait that you are interested in then you can associate those two and show that there are regions of particular genome that are influencing differences in the phenotype of interest. Whereas quantitative genetics, you don’t have to know anything about the genetics; you actually start with the trait itself and then you use, whether or not individuals that are related are more similar in those traits then unrelated. So quantitative genetics is somewhat easier because it is a little more indirect, we don’t have to have the information on the genome in order to use quantitative genetics, so that’s a first step. The second step then is to associate differences in genomes with the differences in the traits.