Which meaning do students, with knowledge of genetics on upper secondary school biology level, attribute to the concept ‘hereditary trait’?

Abstract

The field of genetics education is well researched as nowadays genetic literacy is found very important for the general public in order to be able to make well-informed decisions concerning genetics-related issues. Although several genetic concepts are thoroughly researched, few is published on the concept ‘hereditary trait’. This research studies students’ understanding of this concept. A questionnaire is held under 149 students with knowledge of genetics on upper secondary school biology level, in which students (1) gave a definition of the concept ‘hereditary trait’, (2) gave 5 examples of hereditary traits, (3) classified a list of traits as hereditary (yes/no/maybe) and (4) gave an explanation to their classification. It became clear that students have a limited view on the concept. Students mentioned for the most part only traditional examples of traits which are visible on the outside, independent from environmental factors, have a high variance within a population and do not change over time, such as: eye colour, skin colour and hair shape. They do recognize that hereditary traits are inherited or passed on from parents to their offspring and that they are coded in DNA/genes/chromosomes, but many students do not consider traits as hereditary which are also (partly) influenced by environmental factors, are not visible on the outside of an organism, with no variance within a population, are dynamical (change over time) and are on lower organisational levels which influence the chance or sensitivity to a certain trait or disease (biomarkers). Criteria to exclude these types of traits were mainly: if there is no variation within a population, if they are (partly) influenced by environmental factors or if it is caused by a mutation. Furthermore, a few misconceptions became clear. The results have implications for genetics education.