dna fingerprinting
.... It can be done ether chemically or mechanically. To separate the DNA chemically is done by using a detergent to wash the extra material away. Applying large amounts of pressure to squeeze out the DNA is how DNA is separating by the mechanical method. The separated DNA is then cut into different sized pieces by an enzyme. To sort the DNA by size requires a process called gel electrophoresis. The DNA is pored into a gel and an electrical charge is added. The gel has a negative charge at the bottom and a positive charge at the top. Since the DNA has a slightly negative charge it is attracted to the bottom. The smaller pieces are able to move faster so the move to the bottom of the gel first. Followed by the bigger pieces of DNA. This process will separate the DNA by size. The next step of the southern blot test is to denature the DNA. This process is done by heat or chemically to separate the strands of DNA to leave them single stranded. To blot the DNA is done by applying the gel to a sheet of nitrocellulose paper then baked to permanently attach the DNA to the paper. The southern blot is ready to be analyzed In order to analyze the southern blot a radioactive genetic probe is needed. A radioactive genetic probe is used to make a hybridization reaction with the DNA. A radioactive probe is a singled stranded of DNA this could evidence from the scene of a crime. When the DNA and the probe are added together if the two bind than the probe matches the DNA sample. There are many advantages as well as disadvantages to DNA fingerprinting. One of the most wide spread use of DNA fingerprinting used today is for criminal identification and forensic evidence. Any DNA isolated from blood; hair, skin cells, or other genetic evidence left at the scene of a crime can be compared with the DNA of a criminal suspect. This can prove whether a person is guilty or innocent in a court of law. DNA fingerprinting can also be used to establish the identity of a homicide victim from DNA found on the body. The U.S. government is also looking at using ...