Late last night, a crime was perpetrated by a heinously evil individual. Luckily
ID: 29729 • Letter: L
Question
Late last night, a crime was perpetrated by a heinously evil individual. Luckily, they left behind a sample of DNA. Describe in detail how we will determine who did it amongst a crowd of suspects. Pictures and text are ok.Explanation / Answer
Samples for analysis in this type of case might include a sample of the blood left at the crime scene along with reference blood samples taken from a male suspect. In the laboratory, the testing of the crime scene sample and the reference blood samples would be conducted with identical protocols. Reference samples would, however be tested separately from crime scene samples, so as to eliminate any possibility of contamination of the crime scene samples. Now the following is done: >> the cells were broken apart and the DNA was purified from the other contents >> the amount of testable human DNA recovered was determined >> the PCR process was conducted in order to isolate 14 areas of DNA, mark them for detection, and make numerous copies >> one of the areas determines gender, the other 13 areas are STR’s [STR’s are areas on the DNA at which individuals may have different lengths of a particular pattern of A’s, G’s, T’s, and C’s] >> the lengths of these areas are determined using capillary electrophoresis Once this long process has been completed, the results obtained for the crime scene sample are compared to the results obtained for the reference blood samples. If the suspect’s DNA profile matches the DNA profile of the crime scene bloodstain, he is marked as the one who committed the crime
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.