Restriction Enzymes Chapter 12

Genetic Engineering Making changes to the DNA code Geneticists have learned to: Read DNA Cut DNA into small pieces (restriction enzymes) Copy the pieces (PCR) And put them back together (in any order) Manmade life exist

Recombinant DNA DNA is removed from the cell DNA is cut into pieces Restriction Enzymes recognize specific base sequences and cut the DNA at those bases The exposed bases are “sticky ends” Genes are removed or added to the sticky ends

Recombinant DNA http://www.youtube.com/watch?v=-sI5vy-cD2g

Crime Scene Investigation (CSI) Geneticists in CSI labs use restriction enzymes, PCR, and gel electrophoresis to compare the DNA found at crime scenes to suspects’ DNA

CSI A woman dressed in black and wearing a ski mask and gloves robbed McDonalds October 11th on the corner of San Marcos Blvd. and Knoll Rd. A witness said the perpetrator (perp) cut herself on the corner of a table on the way out CSI Investigators examined the table and got a sample of the perp’s skin

Suspect 1 - Shannon A couple of hours later a women dressed in black was found limping down Via Vera Cruz near the Fish House Restaurant Police apprehended her and brought her down to the station for questioning She claimed to have skinned her leg getting out of her car The suspect had a lot of cash in her purse, which she said she made in tips at her job The police got a DNA sample from the suspect by using a cup she drank water from

CSI Was it Shannon? Criminal’s DNA Suspect 1’s DNA

Suspect 2 - Morgan Another woman was arrested for drunk driving that same night When officers saw a cut on her leg they brought her in for questioning She wasn’t dressed in black and she didn’t have any money on her She said she was alone at her apartment at the time of the crime The police got a DNA sample from the suspect by collecting a used cigarette butt.

CSI Was it Morgan? Criminal’s DNA Suspect 2’s DNA