Gene cloning is an incredible process! I put a picture of it to the left. The process starts with a bacterial cell and a cell containing the DNA you wish to be replicated. Bacterial cells have certain, short, circular pieces of DNA called plasmids that replicate separately from the rest of the bacterial genome, and these will be what we need to help replicate some DNA. In order to clone the DNA we want to clone, we have to insert it into the plasmid. We will do this with a restriction enzyme - an enzyme that cuts DNA very specifically at restriction sites and cuts DNA in an identical, uneven manner, leaving short single-stranded DNA strands sticking out of either end. These strands are called sticky ends - I put a picture of them to the left as well. These sticky ends help the two strands of DNA grab hold to each other. The restriction enzyme cuts both the plasmid and the required gene of interest from the DNA. Then, the plasmid and gene of interest are combined. Our dear friend DNA Ligase then joins the molecules together, creating a recombinant DNA plasmid. This plasmid is then reinserted into the bacterium, which reproduces. The genes produced may then be inserted into other organisms or the proteins harvested by the gene may be used directly. Isn't that fascinating?

Gel electrophoresis is a method that separates macromolecules based on size, electrical charge, and other properties. On the right, I have included a picture of the final results of gel electrophoresis and what the process looks like. For this process, you need a gel electrophoresis chamber, a specific type of gel called agarose gel, and DNA. You place the DNA into little wells at the end of a tray filled with agarose gel and leave it for a while. Once you come back, you should see little bands in the agarose gel - amazing! The way the chamber works is quite cool. It has a positive charge at the opposite end of the chamber from the DNA, which is negatively charged. The DNA flows through the agarose gel, and heavier and larger strands of DNA end up traveling slower then faster strands of DNA, creating those bands. You can place multiple people's DNA in the tray, and if their bands line up with the one on the crime scene, they are pretty suspicious if I do say so myself.

PCR, or polymerase chain reaction, is a technique by which a specific segment of a DNA molecule can be targeted and amplified. The process is divided into three parts: denaturation, annealing, and elongation. During denaturation, the target DNA sequence is separated by heat at temperatures of 94 degrees C. During annealing, primers bond with the ends of the target sequences at around 52 degrees C. And lastly, during elongation, DNA polymerase adds molecules, creating two new strands of DNA. This cycle can repeat many times, generating many times the amount of DNA over just a few hours. Isn't that amazing?