## Module 4 Making a Hypothesis

Now that you have a neatly labeled photo of your gel, it’s time to interpret the results! Refer to the figure on page 18 of the manual; there’s also very useful text there. Does the pattern in your digested lane match the pattern shown for tt nontaster, TT taster, or Tt taster? (If it doesn’t match any of them, be sure to talk to an instructor. It’s possible something went wrong, but also possible that you have one of the rare TAS2R38 alleles rather than one of the two common ones.)

Once you identify which pattern you have, you can make a hypothesis. A hypothesis is “a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation” (Google dictionary). The limited evidence you have is from your gel. If your digested gel pattern matches tt nontaster, the logical hypothesis would be “I will not be able to taste PTC”. Then, you can test that hypothesis by sampling the PTC paper, and seeing if you taste bitterness.

This is of course a simple hypothesis, easily tested. Keep in mind that testing hypotheses, and the theories that arise from them as you gain more evidence, is how we gain scientific knowledge. Below is a video describing what is known as “the most beautiful experiment in biology”, the Meselson and Stahl experiment. Watch to see what they did, what they found out, and how the results have influenced the development of biotechnology.

### Watch