How Is a Statistical Link Established Between a Human Outcome and a Genetic Variant?

The objective of this article is to provide a nontechnical and intuitive introduction to the basic concepts and techniques that are used to establish statistical connections between genetic variants and human phenotypes. Depressive symptoms and delinquent behaviors that are of interest to sociologists are a subset of such human phenotypes. This article focuses on basic linkage analysis and association studies, the essential ideas behind the methods, and a very limited amount of molecular genetics needed for understanding the ideas. The article is written with those social scientists in mind who are interested in the topic but not yet ready to engage the vast and rapidly developing primary literature (journal articles).