A 3D-printed Sanger sequencing activity addresses student misconceptions.

The process of Sanger sequencing can be a challenging and unintuitive concept for students to master. In order to improve student learning, we developed a hands-on Sanger sequencing activity using 3D-printed models to incorporate tactile learning. These 3D models and the accompanying activity demonstrate the differences between gene amplification polymerase chain reaction (PCR) and Sanger sequencing, including the purpose and function of dNTPs and ddNTPs, both in terms of building and terminating the chain and in how the DNA sequence is read. After completing the activity, students self-reported high levels of both learning and enjoyment from the activity. Students were also asked to discuss what misconceptions they had prior to this activity that were addressed and provide suggestions for improving this activity. A majority of the misconceptions are related to the function and differences between dNTPs and ddNTPs, with others related to the function of primers, the high-quality region of sequencing, and the purpose of DNA fragment sizes. Overall, student responses indicate that this activity was enjoyable, improved student learning, and addressed specific misconceptions regarding Sanger sequencing. The use of online dice rolling software or additional computational analysis was a common suggestion from students to improve this activity further in future semesters.