This study investigates the role of the discursive process in the act of scientific knowledge building. Specifically, it links scientific knowledge building to risk perception of Genetically Modified Organisms (GMOs). To this end, this study designed and implemented a three-stage argumentation programme giving pre-service teachers (PSTs) the opportunity to consider, discuss and construct shared decisions about GMOs. The study involved 101 third-year PSTs from two different classes, randomly divided into control and experimental groups. The study utilised both quantitative and qualitative methods. During the quantitative phase, researchers administered a pre- and post-intervention scale to measure both groups' risk perception of GMOs. During the qualitative phase, data were collected from the experimental group alone through individual and group reports and an open-ended questionnaire. T-test results showed a statistically significant difference between the experimental and control groups' risk perception of GMOs. Qualitative analysis also revealed differences, for example, in PSTs' weighing of the pros and cons of scientific research demonstrating positive results of GMOs. In addition, PSTs' acceptance of GMOs increased. Consequently, this study suggests that developing familiarity with scientific enterprise may play an effective role in adopting a scientific perspective as well as a more balanced risk perception of GMOs.