This case aims to strengthen students’ understanding of molecular biology concepts through study of Fragile X Syndrome (FXS). Students begin by learning the cause and phenotypes of FXS and related conditions. Students then apply genetics knowledge to describe the inheritance of FXS. Knowledge of the central dogma of molecular biology helps students understand the impact of genetic and epigenetic changes on expression of the Fragile X mental retardation gene 1 and the impacts of the loss of the Fragile X Mental Retardation Protein on other protein production. As one example of the latter, students look at alterations in metabolic enzymes and consider ways to mitigate the phenotype, proposing treatments for FXS. Throughout the case, students are pointed to a clinical website and scientific literature to build their understanding. This case study also engages students in consideration of diversity and inclusion in conveying, interpreting, and acting on scientific information. Overall, this case can help students connect biological concepts to a real-world application while developing their abilities to think critically and comprehend scientific information.

Primary Image: “Fragile X metaphase spread,” showing human chromosomes with the Fragile X site highlighted with an arrow. This image was accessed via Creative Commons and available under license CC BY 4.0 (provider Europeana, source Wellcome Collection).