This study investigates Swedish teachers’ use of language when teaching genetics in grade nine (students 15-16 years old). Mendelian genetics comprises a substantial part of the genetics taught in many classrooms, including the central relation between the gene and trait concepts. This relation has been identified as a significant problem in teaching and learning genetics, but few satisfactory explanations of its difficulty have been suggested. Thus, the primary objective of the study is to reveal how teachers explain and relate gene and trait (i.e. gene function) while teaching Mendelian genetics, in order to shed light on this problem. Four teachers were observed and recorded through a whole sequence of genetic teaching. The empirical data consist of records of their communications during 45 lessons. Their verbal communications were analyzed using a linguistic framework called thematic pattern analysis. The linguistic analysis of teachers’ talk in action revealed that nuances in their spoken language conveyed four major categories of meanings regarding the gene-to-trait relationship: genes control traits, are identified by traits, have traits or are traits.  The results also reveal a common use of an old word, anlag (from the German word Anlage), in the teachers’ references to the meaning of both gene and trait. This study thus highlights several linguistic challenges in the teaching of Mendelian genetics that might affect students’ learning. Moreover, the study exemplifies how a linguistics methodology can be used to investigate science teaching, an approach heavily called for, but rarely used in published empirical studies.

This study investigates Swedish biology teachers’ inclusion of proteins when teaching genetics in grade nine (students 15-16 years old). For some years there has been a call for the attention of proteins in teaching genetics as a mean of linking the concepts gene and trait. Students are known to have problems with this relation because the concepts belong to different organizational levels. However, we know little about how the topic is taught in the classroom and therefore this case study focus on how four teachers talk about proteins while teaching genetics, and if they use protein as a link between micro and macro level. The four teachers were observed and audio recorded during entire genetics teaching sequences, 45 lessons in total. The teachers’ verbal communication was then analyzed using thematic pattern analysis, which is based in systemic functional linguistics (SFL). The linguistic analysis of teachers’ talk in action revealed great variations in both the extent to which they used proteins in explanations of genetics and the ways they included proteins in the linkage between genes and traits. Two of the teachers used protein as a link between gene and trait, while two did not. Three of the four teachers included instruction about protein synthesis. The common message for all teachers was that proteins are built, but none of the teachers talked about genes as exclusively encoding proteins. Our results show some possible examples of how proteins could be used in teaching genetics at this age level. However, they also suggest that students’ common lack of understanding of proteins as an intermediate link between gene and trait could be explained by shortcomings in the way the subject is taught.