Exploring the relationship between genotype and phenotype using yeast alcohol dehydrogenase 1.

Area of Science:

• Molecular Biology
• Genetics
• Biochemistry

Background:

• Project-based learning enhances student engagement and critical thinking.
• Understanding the genotype-phenotype relationship is fundamental in cell biology.
• Traditional lab courses may not fully integrate diverse molecular techniques.

Purpose of the Study:

• To design and implement a 7-week laboratory project for a sophomore cell biology course.
• To reinforce the relationship between gene sequence (genotype) and protein function (phenotype).
• To utilize yeast alcohol dehydrogenase I (ADH1) as a model system.

Main Methods:

• Students performed site-directed mutagenesis on the ADH1 gene to create a specific mutation (H44R).
• Mutated plasmids were propagated in E. coli, sequenced, and reintroduced into yeast.
• Phenotypic analysis involved assessing yeast growth on selective media with allyl alcohol.

Main Results:

• The introduced H44R mutation conferred resistance to allyl alcohol, demonstrating a clear genotype-phenotype link.
• Student performance improved across all learning objectives, as evidenced by pre- and post-tests.
• 98% of students recognized the integration of multiple techniques in scientific inquiry.

Conclusions:

• The multi-week laboratory effectively developed students' understanding of the scientific process.
• Students gained practical knowledge of molecular techniques and gene-to-protein function relationships.
• The project provided an engaging and effective learning experience, with 84% finding it more engaging than other labs.