Ben Benson, who is an Educational Research Specialist from Sanford Medical School, extended an invitation to the EAGLE Center science program to form a science partnership.
Benson brought laboratory equipment and supplies to perform a DNA gel electrophoresis. The DNA was extracted from patients diagnosed with cancerous tumors, and from healthy subjects. The DNA samples were digested with restriction enzymes to isolate the region of DNA coding for the p53 gene, which helps prevent cancer but has a high incidence of mutation in cancer cells.
Benson mixed the samples with dye so that the DNA strands would be visible in the gel. He also described how the (agarose) gel was prepared, and how the equipment (electrophoresis apparatus) worked. Students put the DNA samples into the gel which was placed in an electrolyte solution and connected to positive and negative electrodes. Electrical current was then run across the gel. After the current ran for an hour, Mr. Benson placed the stained gels in an ultraviolet light box where the DNA glowed, showing the separation of DNA fragments by size; the smaller pieces of DNA traveled farther, while the longer pieces of DNA traveled less.
Patterns found in the test results allowed for comparison of normal DNA containing the functioning p53 gene to mutated p53 samples. Each person has 46 chromosomes or 23 pairs, one set of chromosomes from the mother and one from the father. The results showed one sample with two mutated genes obtained from a tumor, a person who had one mutated gene and one normal functioning gene, and a person with two copies of the normal gene.
Students prepared for Mr. Benson’s visit by first studying their own DNA, which they extracted from cells from the inside of their cheeks. The DNA they extracted was put into a vile that they can now wear as a necklace. They also learned about the steps of DNA replication, transcription, and translation. Using paper models, students also learned the processes of performing polymerase chain reactions (PCR), restriction digests, and cloning bacterial plasmids with human insulin genes.
We are thankful for Mr. Benson providing the opportunity for students to experience one of the foundational procedures used in DNA analysis. Working with advanced lab equipment would be a privilege to any high school student, and we are honored to have been chosen by Mr. Benson as a host school for his outreach program. Use of the p53 gene was not only informative, but gave students exposure to cutting edge scientific research. All present stated that they learned from and enjoyed the activity, including one student describing the experience as “life changing”.