Intoduction: (a) Restriction enzymes, which come from bacteria, are used in DNA profiling. These enzymes work best under specific buffer and temperature conditions. They act like scissors and cut the DNA according to its recognition of sequences and base pairs. This happens on a restriction site which is what biologists look at to help them identify someones DNA. The DNA that is seperated and observed is done through the process agarose gel electrophoresis. This process organizes the DNA fragments by size and put on and agarose gel slab and then has an electric current pass between the elctrodes. By having this done, the fragments of DNA will be drawn to the positive pole which will allow all the fragments of the same size to form into bands which is seen after the DNA is stained. To compare DNA of different individuals to others, radioactive probes are needed. They recognize and pull together the specific sequences of nucleotides. Evidence for DNA fingerprinting is easily obtained through any material that might contain DNA. Population genetics and genetic statistics are two factors that can possibly aggect the relability of DNA profiling. DNA profiling is used in many other ways besides forensics. Some of the other researches DNA profiling is used for are food identification, the identification of human remains, paternity testing, and the identification of human remains.
(b)The objective of this lab is to identify the criminal by using DNA profiling. We will use the DNA of five suspects to see which of them did the crime. We will be able to observe the DNA fragments and match it up the DNA from the crime scene.
(c)The restriction enzymes will cut the DNA at its palindromes. Then the different lengthed fragments of DNA will be generated which will be the DNA fingerprint. Then we will run a gel and stain the DNA to figure out and observe the DNA and match it up to the crime scene DNA.
(d) In lane 1, the DNA size marker is a control for electrophoresis and will show if this process worked or not.
Results: Once the gel was stained overnight and drained, it showed that lane 5 and lane 2 matched. Lane 2 is the crime scene DNA and lane 5 is suspect 3's DNA.
Discussion: (a) Because of the results, out of the five suspects, katie is the criminal. Her DNA matches the DNA found at the crime scene.
(b)A possible error could have been that when pipeting the different DNA's into the lanes, we could have been careless to put them into the right lane which could lead to the identification of the wrong suspect.
