DNA Extraction Lab

      In this lab we asked the question: How can DNA be separated from cheek cells in order to study it? We found that we can extract DNA through a three step procedure of homogenization, lysis, and precipitation. We collected the cells with gatorade and added salt. We then added soap to lyse, or rupture, the cell membrane so all the contents of the cells released into the gatorade. We then added pineapple juice, which is a protease that breaks down the histones (proteins) that the DNA wraps itself around. Lastly we added a nonpolar liquid, alcohol, which made the polar DNA separate from the gatorade solution, successfully extracting DNA from our cheek cells.

     

      While our observations supported our hypothesis, there could be possible errors due to failure of properly inverted the test tube to mix the contents. If the tube was inverted too quickly, then air bubbles could have formed, and according the information about DNA extraction, air bubbles can get caught in the double helix structure. In the procedures I recommend saying to invert the tube slowly. Failure to add the alcohol in could also cause errors. If the alcohol was added too quickly, than it would mix with the gatorade, which would not allow for the DNA to separate out into a polar solution. I recommend to hold the test tube at as much of as angle as possible and to pour the alcohol very carefully and slowly.

      This lab was done to demonstrate the process of DNA extraction and what happens to the DNA through this process. From this lab I learned how to extract DNA with materials that anyone has access to. Based on my experience from this lab, if I ever entered a field like genetics or forensic science, I could use this procedure to extract DNA from important or useful sources.

A clump of DNA