Upper Sixth Students Analyse Their DNA

Our upper sixth students learned more about genetics by analysing their own DNA samples for the presence of an allele associated with taste perception, the molecule PTC (phenylthiocarbamide). This molecule is known to give a bitter taste to certain foods like coffee, sprouts, and broccoli.

The analysis process commenced with DNA extraction, followed by the amplification of the gene using Polymerase Chain Reaction (PCR). Subsequently, the samples underwent treatment with restriction enzymes, which selectively cleave only one allele. Finally, DNA fingerprinting techniques were used to determine the length of the cut fragments, providing insight into the genetic makeup related to taste perception.

At the start of the session, students participated in a blind taste test to see how they responded and gauge their initial reactions to PTC. Some couldn’t tell the difference between PTC paper and the control paper, while others scrunched their faces at the bitterness.

The pivotal question remains: will the DNA fingerprinting match what taste they experienced?