GEL ELECTROPHORESIS

STEPS

FIRST STEP

• Take different DNA samples and expose them to the same restriction enzyme to cut the DNA into fragments.
• (This creates restriction fragment length polymorphism RFLP)
• These are fragments of DNA having different lengths.

SECOND STEP

• Then take the DNA RFLP's and load them into the agar gel.
• Turn on the electricity because DNA is negatively charged due to the phosphate backbone.

THIRD STEP

• The RFLP's will separate according to the length/size of the fragments.
• A) big pieces move slowly through the gel.
• B) small pieces move quickly through the gel.

FINAL STEP

• Stain the gel with Carolina Blue to see the DNA fragments within the gel.
• The DNA bands create a unique "fingerprint" of the individual's DNA.
• 1) 1 in 70 trillion genetic possibility of identical copy. (Only 7.5 million people on earth)

FINGERPRINT TECHNOLOGY

• DNA fingerprinting didn't exist until the early 1980's.
• Your fingerprints are unique unless you have an identical twin.
• Your DNA fingerprint can be found by just dusting for prints.
• To find a DNA fingerprint, a scientist has to first take the DNA out of the nucleus of a cell.
• The goal is to analyze the DNA in a way that shows scientists the tiny differences in the DNA of different people.

FINGERPRINT CONTINUED

• In the past, scientists used a technique called RFLP.
• RFLP analysis needs a lot of DNA so scientists found a way to use less DNA.
• They worked out a method called micro-satellite analysis.

THE END