1. Genetic engineering

2. Genes get moved within or between chromosomes
Naturally:
__________
______ cuts and moves genes (transposons)
E.g., pigment genes of Indian corn
Artificially:
________ fragments
Genes are moved with restriction enzyme tools
E.g,. Human _____ gene into bacteria
Engineering > gene transplants

3. Cut and Paste technology ________ enzymes: DNA cutting tools
Normal function: attack foreign ____
“Restrict” foreign DNA by ______________
Cut at a specific __________ sequence on DNA:
cut v
CGAATTCA
GCTTAAGT
segment of
DNA
Restriction
sequence
Sketch 1

4. Cutting creates Restriction _________
Fragments have single-stranded ‘_________’
fragments
sticky ends
AATTCA GT
CGAATTCA
GCTTAAGT
cut
GCTTAA CG
Sketch 1

5. Fragments can be ‘______’ onto other strands of DNA
Must cut “target” DNA with ____ restriction enzyme
Makes sticky end of target ___________
AATTCA GT
fragment
TTTT
GCTTAA
AAAACG
“Target” DNA
Sketch 2

6. Sticky ends hydrogen-bond readily
AATTCA GT
TTTT
GCTTAA
AAAACG
Sketch 2

7. Sticky ends hydrogen-bond readily
AATTCA GT
TTTT
GCTTAA
AAAACG
Hydrogen bonds
Sketch 3

8. But sugar-phosphate backbones remain un-bonded
Bonded with DNA ______
Resulting DNA strand = __________ DNA
A combination of DNA from multiple _______
AAAACG
AATTCA GT
TTTT
GCTTAA
Sketch 4

9. C.R.I.S.P.E.R. DNA editing technology
(Clustered Regularly-interspaced Short Palindromic Repeats)
“The most powerful biological tool ever known”
Works like a word processor “_____________” function
Much cheaper and faster than existing techniques
First used to edit human genes in 2014
Will soon cure genetic diseases, including cancer
But opens the door for “designer” ______

10. Bacterial origins of CRISPER
Basic mechanism was discovered in E. coli ______
Bacterial defense against _______
Bacterium stores bits of _____ DNA in its own DNA
Allows it to _______ and destroy a virus
Human immune system has a similar mechanism
“B” lymphocytes store bacterial surface ______
If bacterium, is re-infected:
___ genes make 2 kinds of proteins (enzymes):
- ______ to unzip viral DNA
- _______ to cut (destroy) viral DNA of the virus
If viral DNA is a new type:
Cas proteins ____ viral DNA ____ bacterial DNA

11. CRISPER Cas9 gene editing system
Cas9 protein
CRISPER Cas9 gene editing system
protein
Nuclease “scissors”
tracrRNA
____ crRNA in place
crRNA
____ for target sequence

12. Function:
1) Introduce DNA with
“target” sequence
specific to Cas9
2) Target aligns with crRNA
3) Cas9 nucleases cut target
Use:
1) Replace crRNA-trcrRNA complex with gRNA
“_____ RNA”, ___-made for a given task
Has code for whatever gene you want to edit
2) Cas9 then cuts out the target gene sequence
3) Additional enzymes can _______ that gene with something else
E.g., better form of the gene; type of gene ______

13. Older types/uses of genetic engineering
1. Gene sequencing:
To determine the ________ sequence of genes
Uses:
Identify ________ versions of a gene
Determine entire __________ of organisms:
Gemone of many species has been sequenced
2. DNA Fingerprinting
Uses: distinguish between unique genetic _____
E.g., between individuals, species, or larger taxa
Individuals have slight differences in genetic code
E.g., alternate _______

14. 3. Transgenic organisms
Contain genes from other sources
E.g., implanting desirable traits in crop plants
Certain bacteria naturally implant genes into plants
E.g., _________ causes tumors in plants
Technique:
a. Add a gene to such a bacterium’s DNA
b. Allow bacterium to implant gene into plant DNA
Natural ‘___________’ DNA
c. “_______” cells from this plant
Each cell becomes a plant – a _____

15. Currently, genetically modified (GM) crops contain:
___________ proteins
E.g., ____ protein from Bacillus bacteria
Damages gut lining of ______
_________ proteins
strawberries
Anti-freeze proteins
E.g., isoform HPLC 6
-isolated from _____
-injected with Agrobacterium

16. ___________ resistance
Allows heavy spraying against weeds
________-ready soybeans (glyphosate)

17. Transgenic animals:
Faster growth
Larger body size
More efficient ______ use (lbs. of flesh / lbs. of food)

18. Political opposition to GM foods:
Many nations now label or ban ‘GM’ foods
(called ‘_____________’ by some)
Consider unknown risks too high
E.g., recombined genes might disperse in _____
Might “_____” to related species