1. DNA fingerprinting is not taking someone’s fingerprint. It is cutting up a DNA strand and separating them by size.

2. Restriction Enzymes Because everyone’s DNA is so similar (there is only a 0.1% difference among people), the easiest way to differentiate between people’s DNA is to use Restriction Enzymes A Restriction Enzyme cuts a persons DNA like scissors, making cuts wherever it recognizes a specific sequence of base pairs The DNA will be cut into fragments with different lengths, forming a strand like this:

3. Agarose Gel Electrophoresis How can we see these different lengths? The answer is a process galled agarose gel electrophoresis. Little things move faster than big things, so the small fragments of DNA will travel farther than the large fragments We put the DNA into the gel box, and we run electricity through them DNA is negatively charged, so it is attracted to the positive force at the other end of the gel box. The DNA fragments are separated by size, with the smaller fragments traveling farther than the larger ones

4. Staining DNA Because DNA is colorless, it is not immediately visible in the gel. Therefore, we will add dye to help see the DNA, and later stain the gels to make it even easier to see After the staining, we should be able to see all the DNA fragments, and be able to match the DNA at the crime scene to the right suspect