Manipulating DNA Notes
Scientists use their knowledge of the structure of DNA and its chemical properties to identify,
study and change DNA molecules.
Tools of Molecular Biology
1. Gel Electrophoresis= creates a fingerprint to
compare DNA from separate sources.
Steps:
a. DNA Extraction (pull out of nucleus)
b. Cutting DNA (with restriction enzymes)
- Restriction enzymes are used to cut
a sequence of DNA.
c. Sequencing DNA (separate by lengthmeasured in bp or base pair)
- DNA is negatively charged.
- The DNA sequence can then be
“read” as the lighter segments will
travel further and faster.
2. Transformation= a cell takes in DNA from another source and combines them together
to make recombinant DNA.
- Recombinant DNA- DNA that is
made by connecting fragments of
DNA from different sources.
- The DNA is cut with restriction
enzymes and glued back together
with ligase.
3. Polymerase Chain Reaction (PCR)- a
process by which scientists can copy a
segment of DNA (such as a gene)
multiple times.
Recombinant DNA
Manipulating DNA
Transgenic organism- One that contains
recombinant DNA.
1. Agriculture- crops that are more
resistant to disease and pests
2. Industry- bacteria that can eat oil,
goats that produce clotting proteins,
fish that grow faster
3. Medicine- bacteria that create
insulin, human growth hormone
4. Research- glowing tobacco plant and glowing monkey for cancer research
Human genome: DNA comes from blood, hair, skin and bodily fluids. Goal is to one day be
able to provide gene therapy, where the bad gene is replaced with a normal gene.
Cloning- A clone is the production of genetically identical cells and/ or organisms.
1. Single cell organisms that reproduce asexually are genetic clones. Example: bacteria
2. Ian Wilmut was the first to clone a multicellular organism in 1997 – a sheep named
Dolly.