1. How do genetic engineers cut DNA? “teeny tiny scissors”

2. What are the “teeny tiny scissors”? In the 1960’s, scientists discovered bacterial enzymes that cut and digest DNA. (why would bacteria have these enzymes??) Different RESTRICTION ENZYMES cut at specific base sequences and can be used to cut any DNA into small fragments

4. …..and that’s how genetic engineers cut DNA!!

5. “teeny tiny scissors” These RESTRICTION ENZYMES can be used to cut human DNA into small fragments. Because everyone’ DNA is slightly different, fragments of different sizes result. This fact is the basis of…….

6. FORENSIC DNA ANALYSIS In 1987, scientists started using DNA technology in forensics. – “DNA fingerprinting” or “DNA profiling” – 99.9% of human DNA is identical…..but since we have 3,000,000,000 base pairs our.1% that is unique accounts for 300,000,000 base pairs!! – Forensic DNA technology has improved greatly. – Forensic DNA technology can be used to exclude suspects only….not to convict.

7. FORENSIC DNA ANALYSIS Micropipettes can be used to move tiny amounts of DNA samples to be analyzed. Today you will get to practice with a micropipette. Your will be practicing moving samples that are 35 μL (microliters) in size. A microliter is 1/1000 of a mL or 1/1,000,000 of a Liter

9. Who Stole Mother MRSA We collected crime scene blood and blood samples from the two suspects. We cut the samples with 2 different restriction enzymes. The blood that doesn’t match the crime scene blood can most likely be eliminated as a suspect.