medical applications
- pharmaceuticals - uses bacterial cells to mass produce certain proteins cheaply
- recombinant genes introduced into bacterial cells
- used to produce insulin, interferon, growth hormones, erythropoietin
- atrial peptides - small proteins to treat high blood pressure
- tissue plasminogen activator - human protein that causes blood clots to dissolve
- hard/expensive to purify proteins produced by bacterial cells
- genetic therapy - started in 1990 in attempt to fix genetic defects
- replaces defective gene w/ working copy
- piggyback vaccine - aka subunit vaccines, used against viruses
- uses DNA of benign vaccinia virus to make vaccines, stimulate immune system
- DNA vaccine - depends on killer T cells instead of antibodies to stop viruses
agricultural applications
- limited number of possible vectors for plants
- Ti (tumor-inducing) plasmids - infects broadleaf plants
- doesn’t infect cereal plants (corn, rice, wheat)
- “Flavr Savr” - has genes that inhibit ethylene production, delaying over-ripening
- nitrogen fixation - converts nitrogen gas to ammonia
- plants use ammonia to make amino acids
- nifgenes - found in symbiotic root-colonizing bacteria
- soil runs out of nitrogen w/o addition of fertilizers
- problems w/ protecting nitrogenase from oxygen
- herbicide resistance - herbicides used to kill weeds, but can also kill plants
- glyphosphate - active ingredient that inhibits EPSP synthetase
- new engineered plants have 20x normal amount of EPSP synthetase, can work even in presence of glyphosphate
- insect resistance - removes need to use so many insecticides
- uses genes for proteins harmful to insects but harmless to other organisms
- transgenic plants - plants w/ altered genes, protected from insects that normally feed on them
- “golden rice ” - used to solve problem of lack of iron in diets
- ferritin gene from beans added to increase iron content
- gene added to destroy phytate (inhibits iron absorption)
- gene for sulfur-rich protein added from wild rice (sulfur needed for iron absorption)
- ordinary rice lacks certain enzymes to finish provitamin A creation
- gene technology replacing natural/artificial selection as means for breeding
risk/regulation - tampering w/ genetics >> possible bad long-term side effects
- gene modifications make crop easier to grow, improves food itself
- screening for allergy problems done w/ genetically altered foods
- pests become resistant to pesticides faster than to genetically altered defenses
- debates over whether consumers should/need to know about genetically modified foods
Subject:
Subject X2:
