Beyond the Central Dogma: Model-Based Learning of How Genes Determine Phenotypes

Area of Science:

• Genetics Education
• Systems Thinking in Biology
• Molecular Genetics Pedagogy

Background:

• Introductory biology courses often struggle to teach complex gene-phenotype relationships.
• Learner-centered, model-based approaches can enhance conceptual understanding.

Purpose of the Study:

• To implement and assess a model-based pedagogy for teaching molecular genetics.
• To evaluate students' acquisition of systems-thinking skills in understanding gene-phenotype connections.

Main Methods:

• Implemented a learner-centered, model-building pedagogy in an introductory biology course.
• Used case studies to elicit student understanding of variation and gene-phenotype determination.
• Scaffolded instruction and assessment to develop hierarchical systems-thinking skills.
• Analyzed student-generated models from exams to track learning progression.

Main Results:

• Student models improved in accuracy, contextualization, and meaningfulness with practice and feedback.
• A significant portion of students (over 25%) still had difficulty linking phenotype to protein function by semester's end.
• The hierarchical scaffolding of systems-thinking skills showed some progress but incomplete mastery.

Conclusions:

• Model-building and case studies focusing on protein function are crucial for teaching gene-phenotype relationships.
• Further refinement of pedagogical strategies is needed to ensure all students grasp the gene-to-phenotype pathway.
• Connecting molecular genetics concepts to observable traits requires explicit instruction on protein roles.