DNA Profiling

[GeorgiaGS]

(Q) DNA samples have been found at the scene of a crime... using your knowledge of molecular biology methods, devise an experimental plan which will enable you to determine which of the potential suspects committed the crime.

I'm a bit confused about what method to use. In my plan i've explained different methods of DNA profiling but then i've got to pick the best one. I thought PCR, Electrophoresis (with agarose gel) and Flourescent tagging would be the best, but i've read only proteins are flourescently tagged. It could be just as straight dorward as PCR, Electrophoresis and southern blotting, but i want to be sure.

If anyone has any idea i would be very grateful if you could let me know. Thankyou

[jonmoulton]

With appropriately chosen primers, PCR should give a limited number of bands. You can visualize these right in an electrophoresis gel with ethidium bromide staining.

There has been a lot of work done on appropriate primer selection for DNA forensics. You might take a look at the searchable index of the Journal of Forensic Science and browse in the General Public Searchable Index for relevant papers. Watch for papers describing short tandem repeat loci (STR), which are used as forensic markers.
http://www.aafs.org/default.asp?section ... ntact_info
http://www.astm.org/DIGITAL_LIBRARY/JOU ... clist.html

Take a look at this page at Oak Ridge National Labs (USA) describing DNA forensics, especially the section "What are some of the DNA technologies used in forensic investigations?"
http://www.ornl.gov/sci/techresources/H ... sics.shtml