We're working on our lab report for Friday, and are struggling trying to find out where to find information on Plasmids vs. human DNA sample and why does the kit use plasmids and not DNA.
If anyone has suggestions for this, it'd be greatly appreciated! Thank you!!!
A: Look in your orange genetics book on page 434.
Plasmid DNAs are smaller DNA molecules that might have only a few cleavage sites (or maybe none) due to their shorter length in base pairs. Human DNA, on the other hand, has a genome size of 3e9 (3 billion) base pairs that would be cut into a million fragments. (Remember we talked about the chance of a cut occurring is ~4e6 = once every 4096 base pairs when there is a six-base restriction site.) Can you imagine doing a DNA fingerprinting lab where there were millions of human DNA fragments versus the few fragments we had with the plasmids? I'll pass.
There are a lot of reasons plasmids are easier to use. Most of which revolve around their ease of ability to replicate, how well they are studied, the known restriction sites and such. I think its also very practical to use non-human DNA in a kit that is going to be sent out across the globe, because one never knows where that information ends up. I'd hate to have my DNA sent out to some creeper that decides to plant it at the scene of a crime for some strange odd reason and end up in jail JUST for volunteering my DNA for a kit to help some youngsters.
