How Can We Help Students Reason About the Mechanisms by Which Genes Affect Traits?

Understanding how genes affect traits is an important part of scientific literacy in the twenty-first century. However, studies have shown the challenges of teaching and learning these multilevel mechanisms. Research in science education has mapped some of the reasons for students’ difficulties and has explored possible approaches to overcoming them. Those studies have found that the way in which genes, proteins and the complexity of genetic mechanisms are presented to students is inadequate. By reviewing some of the literature in the field of genetics education, I identified three milestones in the progression toward a mechanistic understanding in genetics: (a) establishing a correct causal connection between genes and traits; (b) establishing an understanding of genes–proteins–traits mechanisms, and (c) identifying points of regulation and understanding how environmental signals can modulate gene-to-trait mechanisms. In this chapter, I present the identification of these three milestones and propose novel scaffolds for moving along the progression of mechanistic understanding. I also discuss these milestones in the context of genetics learning progression and draw implications for teaching genetics and for future studies in the field.