BIO 240 Crime Scene Forensics Worksheet
BIO 240 Crime Scene Forensics Worksheet Recent
how forensic scientists take advantage of genomic variations in noncoding regions of DNA
the techniques of polymerase chain reaction (PCR) and gel electrophoresis
Introduction: In recent years, law enforcement has been revolutionized by molecular biology. When human tissues are left behind at crime scenes, these tissues can be collected and processed to yield samples of DNA, which can then be treated to isolate specific DNA fragments that are highly variable in the human population.
Which band pattern among Lanes 3 to 6 seems to be the closest match to the band pattern in Lane 2, where the crime-scene DNA fragment was loaded? Which suspect appears to be the culprit?
What is the molecular weight (in base pairs) of the fragment in Lane 2 (DNA from the crime scene), Lane 3 (Suspect 1), Lane 4 (Suspect 2), Lane 5 (Suspect 3), and Lane 6 (Suspect 4)?
Part C
How does analyzing DNA profiles using the gel electrophoresis tool allow you to draw both qualitative and quantitative conclusions about the likely identity of the suspect in this case?
Judging by the sizes of the fragments you measured in Part C, about how many repeats of the 16-base-pair sequence would you expect to find in each of the suspect’s genomes?
In this lab activity, you targeted just one fragment of DNA to build the DNA profile of each suspect and the crime-scene sample. Real-world DNA profiles target multiple fragments.
What is the advantage of targeting more than one fragment and having each DNA profile feature multiple bands?