Identical Twins, Identical Fates?
An Introduction to Epigenetics
The Jackson Laboratory for Genomic Medicine
This case tells the story of Elise, a college freshman whose identical twin sister has recently been diagnosed with schizophrenia. Elise is concerned about her own risk for developing this disease. Through her research and interactions with a physician, students are introduced to the topic of epigenetics and learn about the data supporting an epigenetic contribution to this psychiatric disorder. This case was designed for a sophomore-level molecular biology course for majors and could easily be adapted for an undergraduate genetics course. The case may also be applicable in a course that covers biological psychology. Students should have a basic knowledge of Mendelian inheritance patterns and a good understanding of the structure of DNA and its packaging within the cell (particularly the role of histone proteins and chromatin). The case also provides an opportunity for students to examine figures and graphs from the primary literature.
- Compare and contrast genetic and epigenetic modes of inheritance.
- Describe how epigenetic modifications lead to changes in gene expression.
- Describe the various epigenetic modifications that can occur to both DNA and chromatin, and predict the most likely effect of those modifications on gene expression.
- List possible genetic and non-genetic causes of schizophrenia.
- Explain how epigenetic factors could lead to different gene expression patterns in identical twins.
- Describe how aberrant DNA methylation might play a role in the development of schizophrenia.
- Describe how drugs that influence epigenetic modifications, such as DNA methylation, could potentially be used in the treatment of schizophrenia.
KeywordsEpigenetics; DNA; schizophrenia; mental health; twins; twin studies; histones; DNA methylation; chromatin; reelin; graphs; data analysis
Educational LevelHigh school, Undergraduate lower division, Undergraduate upper division
Type MethodsAnalysis (Issues), Discussion, Interrupted
Subject HeadingsMolecular Biology | Genetics / Heredity | Biology (General) |