TITLE: Identification of DNA by Restriction Fragmentation Patterns
AUTHOR: Sheela Agrawal
SCHOOL: Joseph Case High School
SCHOOL ADDRESS: 70 School Street, Swansea, MA. 02777
The main objective of this project was to identify DNA by restriction fragmentation patterns, as is the case with DNA Fingerprinting. One practical application, specific to this experiment, is found in the field of forensic analysis.
Experimentation involved setting up a hypothetical scenario in which DNA was collected from a crime scene. This sample was then cut with special enzymes known as type II restriction endonucleases and subjected to get electrophoresis in which fragment separation rate is inversely proportional to fragment size. The resulting patterns were then compared and contrasted to the restriction patterns of two suspect whose DNA was cut with the same endonucleases. Dissimilar patterns between a suspect and the sample completely exonerated that suspect from physically committing the crime. Taking into account population genetics and probability, similar banding patterns between the sample and a suspect do not necessarily mean conviction however. Two trials were run in order to confirm the results. The results in turn were compared to an ideal results schematic.
Based upon the results I concluded that restriction fragmentation patterns can identify DNA. Also, in order for the results to be admissible in the courtroom, extreme caution must be taken to prevent contamination or an error in experimental procedure. In addition, from my results the need for more than one restriction endonuclease is eminent, as using only one can provide inconclusive evidence. Finally, future applications of the DNA technology include DNA fingerprinting pets to help protect against pet theft, and also an alternative means of identification for military personnel.