Blog #13

Blog#13 How has DNA changed how we investigate crimes? What are the two main tests? Describe them

DNA changed the way we investigate because it had helped us find the perpetrator through blood, saliva, hair, fingerprints.  PCR only needs little DNA  and it is very cheaper.  PCR is often used because of its efficiency.  PCR uses repeated regions of the DNA and copies it with another region.  Then, it uses primers to indicate a starting point of where the DNA copying should start.

RFLP requires large amount of DNA that is "fresh".  In RFLP, thousands of cells are collected and then cut in the same place with a restriction enzyme. Next, the cut DNA is sorted by size through a gel which allows smaller pieces of DNA to pass through quicker than the larger pieces of DNA. After, another copy of the gel is used to trap the pieces of DNA which is later on treated with probe. Finally, the sizes and how the DNA is distributed is noted down and repeated for many other people.