What can I exactly do with it? Can I find any gene and how does that really work? The video introduced some gels which reveal the DNA bits, but without further info it's not clear how does it find a particular gene. Really awesome stuff anyway.
Amplifying DNA is useful/necessary for all sorts of biological procedures. High concentrations of DNA are needed for efficiently transfecting microbes, for example.
These days, it's also pretty rare that you won't know the complete genome of the species you're working with, and there are free web tools that can help you design unique primers.
there are free web tools that can help you design unique primers.
Tito OpenPCR
In the dry lab, I'm really more of a regular PCR consumer than a regular PCR user, but yeah, my attitude towards PCR is more or less my attitude towards snakes: try to keep a respectful distance :-)
What that means is this: you have a sample of some DNA or protein. Typically it might be only one copy or only a handful of copies. Nothing in bioscience works on tiny copies; you typically need thousands or millions, particularly for operations like dna sequencing. PCR allows you to amplify -- ie copy -- your sample by causing the DNA helix to split from heat, including a polymerase or enzyme that does the replication work, including spare dna bases, then cooling to cause the helixes to reform. It's essentially a doubling operation; you run k heating/splitting/replication/cooling cycles and at the end hopefully have (#{ starting copies }) * 2^k
Doing the previous operation requires a pcr device which very accurately and evenly heats and cools a microtitre plate; the polymerase; something to dump all this into like very clean water; and raw dna base pairs.