Students in Mrs. Hostetter’s AP biology class used new biotechnology equipment during their latest unit on heredity. For the lab, the students observed whether they could taste the compound PTC and then analyzed their DNA to determine whether they were homozygous or heterozygous tasters or non-tasters.
To determine their genotype, students first extracted a high-quality sample of their DNA from their saliva. Then, they used a polymerase chain reaction to make billions of copies of a specific gene, TAS2R38. Once completed, they ran a restricted digest of their DNA and analyzed the products with gel electrophoresis. Finally, they used the pattern of bands to confirm their genotype.
Through the lab, students not only gained valuable skills using the new lab equipment, but also had a chance to see how alterations in a DNA sequence can lead to changes in the type or amount of the protein produced and the consequent phenotype.